STEREO RECEPTION OF AUDIO STREAMS IN SINGLE ENDPOINT WIRELESS SYSTEMS

Disclosed herein, among other things, are systems and methods for obtaining stereo reception of an audio stream by multiple audio devices when only a single endpoint is the intended recipient. A system includes a first audio device and one or more second audio devices. The first audio device receives a first signal from a central device via a first wireless connection, transfers to the one or more second audio devices via a second wireless connection a second signal to enable the one or more second audio devices to eavesdrop on the first wireless connection, receives the incoming audio packet via the first wireless connection, and sends the incoming audio packet to the one or more second audio devices via the second wireless connection. The one or more second audio devices receives the incoming audio packet using the second wireless connection or by eavesdropping on the first wireless connection.

TECHNICAL FIELD

This document relates generally to audio device systems and more particularly to methods for obtaining stereo reception of an audio stream by multiple audio devices when only a single endpoint is the intended recipient.

BACKGROUND

Audio devices, or audio sinks, can be used to provide audible output to a user based on received wireless signals. Examples of audio devices include speakers and hearing devices, also referred to herein as hearing assistance devices or hearing instruments, including both prescriptive devices and non-prescriptive devices. Specific examples of hearing devices include, but are not limited to, hearing aids, headphones, and earbuds.

Hearing devices generally include the capability to receive audio streams from a variety of sources. For example, a hearing device may receive audio or data wirelessly from a transmitter or streamer of an assistive listening device (ALD) or smartphone. Audio information can be digitized, packetized and transferred as digital packets to and from the hearing devices for the purpose of streaming entertainment or other content. However, some wireless protocols include a designation of a single endpoint recipient which can make stereo reception of audio signals at multiple audio devices problematic.

Thus, there is a need in the art for improved systems and methods for receiving an audio stream for hearing devices.

SUMMARY

Disclosed herein, among other things, are systems and methods for obtaining stereo reception of an audio stream by multiple audio devices when only a single endpoint is the intended recipient. A method includes receiving, at a first audio device of multiple audio devices, a first signal from a central device via a first wireless connection, the first signal indicative of an incoming audio packet. The method further includes transferring, from the first audio device to one or more second audio devices of the multiple audio devices via a second wireless connection, a second signal providing information to the one or more second audio devices to enable the one or more second audio devices to eavesdrop on the first wireless connection. The method also includes receiving, at the first audio device, the incoming audio packet via the first wireless connection, and sending, from the first audio device to the one or more second audio devices via the second wireless connection, the incoming audio packet one or more times. The method further includes receiving, at the one or more second audio devices, the incoming audio packet using one or more of the second wireless connection or eavesdropping on the first wireless connection. The method may include playing, using receivers at the first audio device and the one or more second audio devices, stereo audio for a user of the first audio device and the one or more second audio devices, including using a delay at the first audio device, the delay including a transport delay of the second wireless connection and a presentation delay of the one or more second audio devices.

Various aspects of the present subject matter include a system including a first audio device and one or more second audio devices. The first audio device includes one or more first processors programmed to receive a first signal from a central device via a first wireless connection, the first signal indicative of an incoming audio packet, transfer to the one or more second audio devices via a second wireless connection a second signal providing information to the one or more second audio devices to enable the one or more second audio devices to eavesdrop on the first wireless connection, receive the incoming audio packet via the first wireless connection, and send the incoming audio packet one or more times to the one or more second audio devices via the second wireless connection. The one or more second audio devices include one or more second processors programmed to receive the incoming audio packet using one or more of the second wireless connection or eavesdropping on the first wireless connection.

This Summary is an overview of some of the teachings of the present application and not intended to be an exclusive or exhaustive treatment of the present subject matter. Further details about the present subject matter are found in the detailed description and appended claims.

DETAILED DESCRIPTION

The present detailed description will discuss audio devices such as hearing devices and speakers. The description refers to hearing devices generally, which include earbuds, headsets, headphones and hearing assistance devices using the example of hearing aids. Other hearing devices include, but are not limited to, those in this document. It is understood that their use in the description is intended to demonstrate the present subject matter, but not in a limited or exclusive or exhaustive sense.

Hearing devices generally include the capability to receive audio streams from a variety of sources. For example, a hearing device may receive audio or data wirelessly from a transmitter or streamer of an assistive listening device (ALD) or smartphone. Audio information can be digitized, packetized and transferred as digital packets to and from the hearing devices for the purpose of streaming entertainment or other content. However, some wireless protocols include a designation of a single endpoint recipient which can make stereo reception of audio signals at multiple audio devices problematic. Previous attempted solutions to this problem include using acknowledgments between recipient devices prior to sending an acknowledgment to a central source device. However, these previous attempts requires multiple radio systems instead of a single radio system being used in a time division multiplexing solution. In addition, the previous attempts rely upon strict timing requirements via a proprietary protocol to ensure acknowledgments are received in a timely manner.

The present subject matter provides systems and methods for obtaining stereo reception of an audio stream by two or more audio devices or sinks (such as speakers, hearing devices or hearing aids) when only a single endpoint is the intended recipient. The present subject matter provides for use of standard communication protocols to accomplish the task of true wireless connections to multiple audio devices in single endpoint networks. In addition, the present subject matter ensures that packets are received by multiple audio devices without the aforementioned timing requirements, and provides for a greater number of network connections and associated advertisements.

FIG.1illustrates a block diagram of a system100for obtaining stereo reception of an audio stream by two audio devices when only a single endpoint is the intended recipient, according to various embodiments of the present subject matter. The system includes a first audio device104and one or more second audio devices106. The first audio device104includes one or more first processors programmed to receive a first signal from a central device102(or source device) via a first wireless connection110, the first signal indicative of an incoming audio packet. The first audio device104transfers to the one or more second audio devices106via a second wireless connection130a second signal providing information to the one or more second audio devices106to enable the one or more second audio devices106to eavesdrop120on the first wireless connection110. The first audio device104receives the incoming audio packet via the first wireless connection110, and sends the incoming audio packet one or more times to the one or more second audio devices106via the second wireless connection130. The one or more second audio devices106include one or more second processors programmed to receive the incoming audio packet using one or more of the second wireless connection130or eavesdropping120on the first wireless connection110.

The audio devices may include hearing devices, such as hearing aids. Additionally or alternatively, a hearing device104(P1C2) acts as peripheral to a central device102(C1) via a first connection110, such as a basic rate/enhanced data rate (BR/EDR) asynchronous connection-oriented (ACL) connection. The central device102is an audio source, such as a smartphone or media player in a Bluetooth piconet configuration, in various examples. The hearing device104(P1C2) is also configured to act as a central device to a second hearing device106(P2) via a second connection130, such as a Low Energy asynchronous connection-oriented (LE ACL) connection.

The central device C1 in a Classic Bluetooth (BR/EDR) piconet connection110may at any time start an advanced audio distribution profile (A2DP) session with a peripheral device P1C2 (audio device104). The session may start when audio such as music is played or audio for a video is to be rendered, in various examples. Additionally or alternatively, the audio device104transfers link keys, session keys, an identity address, a Bluetooth clock, and a channel map to the second audio device106over the second connection130, such as an LE ACL connection. The channel map is used for a channel hopping system, in various examples. After receiving this information, the second audio device106may receive (eavesdrop on) the audio link (first connection110) between the central device102and the first audio device104engaged in an audio session, the audio session using, for example, an audio/video distribution transport protocol (AVDTP) over a BR/EDR ACL connection.

The second audio device (P2)106does not have guaranteed delivery of audio packets from eavesdropping on the BR/EDR ACL connection. As a precaution to ensure a reliable link for the second audio device (P2)106, an isochronous channel (second connection130) is set up between the first audio device (P1C2)104and the second audio device (P2) device106, in an example. Additionally or alternatively, the first audio device (P1C2)104sends a copy of the audio packet received from the central device (C1)102one or more times to the second audio device (P2)106over the second connection130, such as an LE-S(LE isochronous stream) and/or an LE-ACL connection. Other types of isochronous connections may be used without departing from the scope of the present subject matter. In this manner, the first audio device (P1C2) obtains as many attempts as needed before timing out to receive the audio packet from the central device (C1)102. In addition, the second audio device (P2) device106may receive the audio packet by eavesdropping120on the central device (C1)102to first audio device (P1C2)104connection110and still other opportunities via the first audio device (P1C2)104to second audio device (P2) 106 second connection130. The second connection may include both an LE-S connection and an LE-ACL connection.

Additionally or alternatively, for audio to be rendered synchronously to a user from the first audio device104and the second audio device106(such as left and right hearing aids), a delay is used by one of the first and second audio devices prior to rendering the audio. In one example, the delay includes a presentation delay, and a transport delay. Additionally or alternatively, the presentation delay includes a decoding delay, a buffer delay and a signal processing delay. For example, the first audio device104may delay the playing of audio to account for a transport delay of an isochronous channel (second connection130) between the first audio device104and the second audio device106, and to account for a presentation delay of the second audio device106. In one example, these delays are accounted for in the standard for LE isochronous channels described in core Bluetooth 5.2, for example.

Additionally or alternatively, the A2DP connection maintains a buffer of audio packets to ensure quality of service. The first audio device104and the second audio device106each include a buffer of audio frames and perform a handshake when the audio stream begins to ensure playback of the same audio frame at the substantially the same time, in various examples. The handshake between the first audio device104and the second audio device106is performed each time an audio buffer is depleted, and/or each time a one of the devices is power cycled, in various examples. Additionally or alternatively, the second audio device106is programmed to arbitrate which audio packets, either received directly from the first audio device104or received by eavesdropping on the connection between the first audio device104and the central device102, is stored in the audio buffer of the second audio device106. Additionally or alternatively, the second audio device106uses sequence numbers to track received audio packets. In various examples, the second audio device106uses timestamps to track received audio packets. Additionally or alternatively, the first audio device104can track lost audio packets by recording a number of lost audio frames based on an A2DP protocol, for example, to ensure reception of the lost audio packets by the second audio device106.

Various examples include using a near-field magnetic induction (NFMI) link for the second connection130between the first audio device104and the second audio device106. Other types of connections, such as 2.4 GHz radio connections, can be used for the second connection130without departing from the scope of the present subject matter. In one example, the first audio device104sends a copy of the audio packet received from the central device102one or more times to the second audio device106over an NEW connection. Additionally or alternatively, the second audio device106may skip listening to the second connection130if it is successful eavesdropping120on the first connection110. Additionally or alternatively, the first audio device104and the second audio device106may switch roles with respect to which device is maintaining the first connection110with the central device102and which device is eavesdropping, either to balance power consumption between the devices or to improve link margin for the connections.

The second connection130may be programmed to allow for retransmissions as necessary to ensure a quality link between the first audio device104and the second audio device106. For example, if the second connection130is an LE-S link, the symbol rate can be change between 2 Mbps, 1 Mbps or one of the other allowed LE long range physical layers (PHYs) for balancing reliability, power consumption and bandwidth. Additionally or alternatively, both the first audio device104and the second audio device106may be equipped with dual mode Bluetooth transceivers capable of both Classic and LE modes of operation.

According to various examples, the second connection130(for example, an LE ACL connection) can be used to forward Link Management Protocol (LMP) and logical link control and adaptation protocol (L2CAP) packets received by the first audio device104and the second audio device106. Additionally or alternatively, the first audio device104maintains the BR/EDR ACL connection, and has guaranteed delivery of ACL packets. In this example, the second audio device106will be eavesdropping for these packets, so delivery of the ACL packets is not guaranteed. In this example, the second connection130includes an LE ACL connection to ensure delivery to the second audio device106of all LMP and L2CAP packets as long as the connections are maintained. LMP and L2CAP messages received from the LE ACL connection can be routed to either the Host Application or Controller running on the second audio device106to maintain the connection state in synchronization with the first audio device104.

In various examples, since the same LMP or L2CAP message can be received by the second audio device106, either through the LE ACL connection130or by eavesdropping120, a mechanism to detect duplicate message reception is used. Additionally or alternatively, the second audio device106maintains a record of each LMP or L2CAP packet received over the BR/EDR ACL connection110. In this example, each record is time-stamped using the Bluetooth clock. When the same messages/packets are forwarded by the first audio device104over the LE ACL connection130, these messages/packets also include a timestamp based on a local Bluetooth clock. In various examples, the timestamp is recorded by the second audio device106at the time of reception. Since the Bluetooth clock on the first audio device104and the second audio device106are synchronized by the BR/EDR ACL connection, duplicate packets can be detected by the second audio device106based on the timestamp and message type. The timestamp may also be used by the second audio device106to compensate for the transport delay over the LE ACL connection130if the LMP or L2CAP procedure is time critical. For example, the first audio device104may delay the response to central device102for messages until the second audio device106has acknowledged reception of the messages over the LE ACL connection130. This procedure may avoid race conditions the second audio device106fails to receive messages over the eavesdropping path, resulting in the messages being processed in the incorrect order. The second audio device106may also wait to process time-critical messages until the same messages are also received over the LE ACL connection130. Additionally or alternatively, processing may include decoding the audio encoded within a packet or audio frame. In this manner, both the first audio device104and the second audio device106can be assured to receive the message prior to rendering the audio contained in the packet.

Additionally or alternatively, the LE ACL connection130can also be used to communicate an irreparable loss of synchronization in the connection state of the BR/EDR connections between the first audio device104and the second audio device106. In one example, the central device102may be forced to resend all LMP and L2CAP messages to re-establish protocol connections between all stack layers (LMP, L2CAP, profile layers, etc.). The first audio device104may, disconnect the BR/EDR ACL connection and perform establishment procedures, in various examples. The first audio device104may then transfer the link keys, session keys, an identity address, a Bluetooth clock, and a channel map to the second audio device106to re-synchronize the LMP connection and restart eavesdropping/forwarding of L2CAP and IMP messages. Additionally or alternatively, this method may also be used to restore system state if the second audio device106is power cycled, or if the LE ACL connection to the first audio device104is lost.

The LE-S connection130may be a Unicast isochronous connection in which the Unicast recipient can acknowledge the transmitted packet. Additionally or alternatively, the LE-S connection130may be a Broadcast isochronous connection in which the recipient has no way to acknowledge the receipt of a transmitted packet, in which case unconditional retransmissions may be used by the transmitter of the first audio device104.

The present subject matter provides a method of obtaining stereo reception of an audio stream by two audio devices (or sinks) when only a single endpoint is the intended recipient, via eavesdropping and through the use of a Bluetooth low energy isochronous connection between audio sinks to ensure reception. Additionally or alternatively, the role of the peripheral to the central device can be changed for the purpose of balancing power. Additionally or alternatively, the role of the peripheral to the central device can be changed for the purpose of improving link quality.

FIG.2illustrates a block diagram of a system200for obtaining stereo reception of an audio stream by multiple audio devices when only a single endpoint is the intended recipient, according to various embodiments of the present subject matter. The system includes a first audio device204and one or more second audio devices206,207,208. The first audio device204includes one or more first processors programmed to receive a first signal from a central device202(or source device) via a first wireless connection210, the first signal indicative of an incoming audio packet. The first audio device204transfers to the one or more second audio devices206,207,208via second wireless connections236,237,238a second signal providing information to the one or more second audio devices206,207,208to enable the one or more second audio devices206,207,208to eavesdrop226,227,228on the first wireless connection210. The first audio device204receives the incoming audio packet via the first wireless connection210, and sends the incoming audio packet one or more times to the one or more second audio devices206,207,208via the second wireless connections236,237,238. The one or more second audio devices206,207,208include one or more second processors programmed to receive the incoming audio packet using one or more of the second wireless connections236,237,238or by eavesdropping226,227,228on the first wireless connection210. While three second audio devices206,207,208are depicted, any number of second audio devices may be used without departing from the scope of the present subject matter.

In various examples, the one or more second audio devices206,207,208(or multiple peripheral devices) may or may not be capable of receiving the primary communication between the central device202and the first audio device204. However, the one or more second audio devices206,207,208are capable of receiving either a unicast or broadcast transmission from the first audio device204. In this example, the first audio device204may transmit the relevant channel to each peripheral. For example, the first audio device204may transmit left front information to a left front speaker, or right front information to a right front speaker.

FIG.3illustrates a flow diagram of a method300for obtaining stereo reception of an audio stream by two audio devices when only a single endpoint is the intended recipient, according to various embodiments of the present subject matter. The method300includes receiving, at a first audio device of multiple audio devices, a first signal from a central device via a first wireless connection, the first signal indicative of an incoming audio packet; at step302. The method further includes transferring, from the first audio device to one or more second audio devices of the multiple audio devices via a second wireless connection, a second signal providing information to the one or more second audio devices to enable the one or more second audio devices to eavesdrop on the first wireless connection, at step304. The method also includes, at step306receiving, at the first audio device, the incoming audio packet via the first wireless connection, and sending, from the first audio device to the one or more second audio devices via the second wireless connection, the incoming audio packet one or more times, at step308. The method further includes receiving, at the one or more second audio devices, the incoming audio packet by eavesdropping on the first wireless connection or by using the second wireless connection (e.g., if eavesdropping is unsuccessful), at step310. Various examples of the method include playing, using receivers at the first audio device and the one or more second audio devices, stereo audio for a user of the first audio device and the one or more second audio devices, including using a delay at the first audio device, the delay including a transport delay of the second wireless connection and a presentation delay of the one or more second audio devices, at step312.

According to various examples, the first wireless connection includes a Bluetooth® connection. The second wireless connection includes a Bluetooth® Low Energy (BLE) connection, such as a BLE asynchronous connection-oriented (LE ACL) connection and/or a BLE isochronous stream (LE-S) connection, in various examples. Additionally or alternatively, the second wireless connection includes a near-field magnetic induction (NFMI) connection. The second signal includes link keys, session keys, an identity address, a wireless clock and a channel map, or some combination of one or more of the link keys; session keys, an identity address, a wireless clock and a channel map, in various examples. Additionally or alternatively, the one or more second audio devices are configured to automatically function as the first audio device to improve link quality of the first wireless connection to the central device. Additionally or alternatively, the one or more second audio devices are configured to automatically function as the first audio device to balance power consumption between the first audio device and the one or more second audio devices. The first signal includes an advance audio distribution profile (A2DP) transmission, in an example, including an audio/video distribution transport protocol (AVDTP).

Various aspects of the present subject matter include a system including a first audio device and one or more second audio devices. The first audio device includes one or more first processors programmed to receive a first signal from a central device via a first wireless connection, the first signal indicative of an incoming audio packet, transfer to the one or more second audio devices via a second wireless connection a second signal providing information to the one or more second audio devices to enable the one or more second audio devices to eavesdrop on the first wireless connection, receive the incoming audio packet via the first wireless connection, and send the incoming audio packet one or more times to the one or more second audio devices via the second wireless connection. The one or more second audio devices include one or more second processors programmed to receive the incoming audio packet using one or more of the second wireless connection or eavesdropping on the first wireless connection.

According to various examples, the one or more first processors and the one or more second processors are programmed to play, using receivers at the first audio device and the one or more second audio devices, stereo audio for a user of the first audio device and the one or more second audio devices, including using a delay at the first audio device, the delay including a transport delay of the second wireless connection and a presentation delay of the one or more second audio devices. Additionally or alternatively, the first audio device and the one or more second audio devices include one or more buffers of audio frames. The one or more first processors and the one or more second processors are programmed to perform a handshake to ensure stereo audio playback includes a same audio frame, in an example. The one or more first processors and the one or more second processors are programmed to perform the handshake upon depletion of the one or more buffers, in an example. The one or more first processors and the one or more second processors are programmed to perform the handshake upon power cycling of the first audio device or the one or more second audio devices, in an example. Additionally or alternatively, one or more second processors are programmed to stop monitoring the second wireless connection if successfully eavesdropping on the first wireless connection, Additionally or alternatively, the first audio device or the one or more second audio devices include a hearing assistance device, such as a hearing aid.

The present subject matter provide for improved reception of audio packets by multiple audio devices, by using eavesdropping on a single endpoint wireless connection together with relaying of the audio packets to provide redundancy and ensure proper reception by audio devices that are not engaged in the single endpoint wireless connection.

Machine (e.g., computer system)400may include a hardware processor402(e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory404and a static memory406, some or all of which may communicate with each other via an interlink (e.g., bus)408. The machine400may further include a display unit410, an alphanumeric input device412(e.g., a keyboard), and a user interface (UI) navigation device414(e.g., a mouse). In an example, the display unit410, input device412and UI navigation device414may be a touch screen display. The machine400may additionally include a storage device (e.g., drive unit)416, one or more input audio signal transducers418(e.g., microphone), a network interface device420, and one or more output audio signal transducer421(e.g., speaker). The machine400may include an output controller432, such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc.).

The storage device416may include a machine readable medium422on which is stored one or more sets of data structures or instructions424(e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. The instructions424may also reside, completely or at least partially, within the main memory404, within static memory406, or within the hardware processor402during execution thereof by the machine400. In an example, one or any combination of the hardware processor402, the main memory404, the static memory406, or the storage device416may constitute machine readable media.

While the machine readable medium422is illustrated as a single medium, the term “machine readable medium” may include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) configured to store the one or more instructions424.

Various examples of the present subject matter support wireless communications with a hearing device. In various examples the wireless communications may include standard or nonstandard communications. Some examples of standard wireless communications include link protocols including, but not limited to, Bluetooth™, Bluetooth™ Low Energy (BLE), IEEE 802.11(wireless LANs), 802.15 (WPANs), 802.16 (WiMAX), cellular protocols including, but not limited to CDMA and GSM, ZigBee, and ultra-wideband (UWB) technologies. Such protocols support radio frequency communications and some support infrared communications while others support NFMI. Although the present system is demonstrated as a radio system, it is possible that other forms of wireless communications may be used such as ultrasonic, optical, infrared, and others. It is understood that the standards which may be used include past and present standards. It is also contemplated that future versions of these standards and new future standards may be employed without departing from the scope of the present subject matter.

The wireless communications support a connection from other devices. Such connections include, but are not limited to, one or more mono or stereo connections or digital connections having link protocols including, but not limited to 802.3 (Ethernet), 802.4, 802.5, USB, SPI, PCM, ATM, Fibre-channel, Firewire or 1394, InfiniBand, or a native streaming interface. In various examples, such connections include all past and present link protocols. It is also contemplated that future versions of these protocols and new future standards may be employed without departing from the scope of the present subject matter.

Hearing assistance devices typically include at least one enclosure or housing, a microphone, hearing assistance device electronics including processing electronics, and a speaker or “receiver.” Hearing assistance devices may include a power source, such as a battery. In various examples, the battery is rechargeable. In various examples multiple energy sources are employed. It is understood that in various examples the microphone is optional. It is understood that in various examples the receiver is optional. It is understood that variations in communications protocols, antenna configurations, and combinations of components may be employed without departing from the scope of the present subject matter. Antenna configurations may vary and may be included within an enclosure for the electronics or be external to an enclosure for the electronics. Thus, the examples set forth herein are intended to be demonstrative and not a limiting or exhaustive depiction of variations.

It is understood that digital hearing assistance devices include a processor. In digital hearing assistance devices with a processor, programmable gains may be employed to adjust the hearing assistance device output to a wearer's particular hearing impairment. The processor may be a digital signal processor (DSP), microprocessor, microcontroller, other digital logic, or combinations thereof. The processing may be done by a single processor, or may be distributed over different devices. The processing of signals referenced in this application may be performed using the processor or over different devices. Processing may be done in the digital domain, the analog domain, or combinations thereof. Processing may be done using subband processing techniques. Processing may be done using frequency domain or time domain approaches. Some processing may involve both frequency and time domain aspects. For brevity, in some examples drawings may omit certain blocks that perform frequency synthesis; frequency analysis, analog-to-digital conversion, digital-to-analog conversion, amplification, buffering, and certain types of filtering and processing. In various examples of the present subject matter the processor is adapted to perform instructions stored in one or more memories, which may or may not be explicitly shown. Various types of memory may be used, including volatile and nonvolatile forms of memory. In various examples, the processor or other processing devices execute instructions to perform a number of signal processing tasks. Such embodiments may include analog components in communication with the processor to perform signal processing tasks, such as sound reception by a microphone, or playing of sound using a receiver (i.e., in applications where such transducers are used). In various examples of the present subject matter, different realizations of the block diagrams, circuits, and processes set forth herein may be created by one of skill in the art without departing from the scope of the present subject matter.

It is further understood that different hearing devices may embody the present subject matter without departing from the scope of the present disclosure. The devices depicted in the figures are intended to demonstrate the subject matter, but not necessarily in a limited, exhaustive, or exclusive sense. It is also understood that the present subject matter may be used with a device designed for use in the right ear or the left ear or both ears of the wearer.

The present subject matter is demonstrated for hearing devices, including hearing assistance devices, including but not limited to, behind-the-ear (BTE), in-the-ear (ITE), in-the-canal (ITC), receiver-in-canal (RIC), invisible-in-canal (ITC) or completely-in-the-canal (CIC) type hearing assistance devices. It is understood that behind-the-ear type hearing assistance devices may include devices that reside substantially behind the ear or over the ear. Such devices may include hearing assistance devices with receivers associated with the electronics portion of the behind-the-ear device, or hearing assistance devices of the type having receivers in the ear canal of the user, including but not limited to receiver-in-canal (RIC) or receiver-in-the-ear (RITE) designs. The present subject matter may also be used in hearing assistance devices generally, such as cochlear implant type hearing devices. The present subject matter may also be used in deep insertion devices having a transducer, such as a receiver or microphone. The present subject matter may be used in bone conduction hearing devices, in some examples. The present subject matter may be used in devices whether such devices are standard or custom fit and whether they provide an open or an occlusive design. It is understood that other hearing devices not expressly stated herein may be used in conjunction with the present subject matter.