I have a sat nav in a case on the motorbike, I would like to place a small microphone in the case which I can plug into the lead of a head set installed in my helmet. Ideally I would like to power it from a power pack
Its a Garmin nuvi 57LM. There are no outlets and its not blue tooth. I have thought about removing the back and wiring a female connector for the head set straight to the internal speaker as a last resort.