Hi, I have an A4, 2002, 1.9TDI Quattro, Estate.
I recently bought a new HU for the car (JVC KD - R541E) , stripped the old Audi Concert HU, hooked her up, front speakers are working, but the rear speakers and sub aren't working.
The sound system is BOSE.
I bought an adadpter to attatch all...