A portion of a vestibular prosthesis system comprising: an external coil housing having a skin interface surface configured to lie against the skin of a patient's head behind the outer ear; an external holding magnet contained within the external coil housing and configured to cooperate with a corresponding implant holding magnet located under the skin to securely hold the skin interface surface against the skin over the implant holding magnet; one or more external movement sensors contained within the external coil housing and configured to generate an external movement signal representing movement of the patient's head; an external signal processor in communication with the one or more external movement sensors configured for producing an implant communication signal having an electrical power component and a signal component based on the external movement signal; and an external communications coil arrangement in communication with the external signal processor and contained within the external coil housing in a plane around the external holding magnet and configured to cooperate with a corresponding implant communications coil arrangement located under the skin for transcutaneous inductive coupling of the implant communications signal between the external communications coil and the implant communications coil; wherein the external coil housing and the external holding magnet allow rotation of the external coil housing around a rotation axis that passes through the external holding magnet orthogonal to the skin interface surface; wherein the external communications coil arrangement comprises three or more external coil segments rotationally adjacent to each other around the rotation axis, each external coil segment being independently operable by the external signal processor for coupling the implant communication signal; and wherein the external signal processor is configured to periodically operate a plurality of the external coil segments to quantify rotation of the external coil housing and adjust the signal component of the implant communication signal to offset the quantified rotation. an external coil housing having a skin interface surface configured to lie against the skin of a patient's head behind the outer ear; an external holding magnet contained within the external coil housing and configured to cooperate with a corresponding implant holding magnet located under the skin to securely hold the skin interface surface against the skin over the implant holding magnet; one or more external movement sensors contained within the external coil housing and configured to generate an external movement signal representing movement of the patient's head; an external signal processor in communication with the one or more external movement sensors configured for producing an implant communication signal having an electrical power component and a signal component based on the external movement signal; and an external communications coil arrangement in communication with the external signal processor and contained within the external coil housing in a plane around the external holding magnet and configured to cooperate with a corresponding implant communications coil arrangement located under the skin for transcutaneous inductive coupling of the implant communications signal between the external communications coil and the implant communications coil; wherein the external coil housing and the external holding magnet allow rotation of the external coil housing around a rotation axis that passes through the external holding magnet orthogonal to the skin interface surface; wherein the external communications coil arrangement comprises three or more external coil segments rotationally adjacent to each other around the rotation axis, each external coil segment being independently operable by the external signal processor for coupling the implant communication signal; and wherein the external signal processor is configured to periodically operate a plurality of the external coil segments to quantify rotation of the external coil housing and adjust the signal component of the implant communication signal to offset the quantified rotation.