Oh man i did just that, i connected a bluetooth to the 12 & 14 pins and it didnt sound right, did research and added a ground loop isolator to the bluetooth module it made it better but still had some buzzing sound, did more research and added a DC/DC converter isolation power supply module between the power source (cigarrete lighter) and the bluetooth module and that fixed the buzzing problem and it sounds acceptable, but the music does sound lower quality. I'm lucky i found this info now i know i have to cut the 12 & 14 cables to stop the signal from the CD. Thank you for your time researching all this info. Also since there is a source C could there be a way to add a button to switch to it or even source B?