Patent ID: 7502478

Claim:
An audio playback device interface for interface with an audio headset, said audio playback device comprising: a first load resistance in series between an audio output of a stereo headset driver and a ground, wherein the first load resistance is configured to prevent the audio output from directly contacting the ground when a mono headset plug is inserted into the stereo headset driver to prevent damage to the stereo headset driver by providing a load that prevents the audio output from directly contacting the ground, the first load resistance configured to reduce current draw from a power supply corresponding to the playback device when a mono headset is plugged into a headset jack, wherein the first load resistance is at least equal to the minimum impedance that the stereo headset driver is configured to drive; a second load resistance equal to the first load resistance, the second load resistance in series between a second audio output of a stereo headset driver and a stereo headset jack of an audio playback device; and a blocking capacitor disposed between the stereo headset driver and the first load resistance, wherein the blocking capacitor is configured to filter DC voltage from the stereo headset driver.