So I wanna build a car mount (Mini USB wiring)

[spamftw]

Hey all,

So I've decided to attempt to build a custom car mount, the basic idea is to wire the usb to both charge the device, and to connect it to some exteral speakers glued to the mount to make the directions from Garmin Mobile XT loud enough for me to hear.


Does anyone know if it is possible to both charge the device and recieve audio? And if so is anyone willing to share the wiring diagram for this?

Thanks a ton
spamftw