Hi First timer and got a major hair pulling problem, i have retrofitted my 2007 A4 avant s line with an rnse unit that i bought from Tech toys, this fitted a treat but noticed that it is not recognised by Vag Com when i try to connect, but it worked so left it be. 3 weeks later decided to fit a Harman Becker bluetooth kit bought from poland, kit complete with wiring harness and unit, connected ok but when i make a call or recive a call the person at the other end cannot here me. i have tried swopping the mic wires around in the connector on the bluetooth unit but this has made no difference. I have tried to configure the vehicle with vagcom but it will not connect to can gateway (thought this car would have this) and as i cannot connect to nav i cannot tell the car that it has bluetooth. My question is have i done something wrong or do i have compatibility issue or do i have a faulty unit. Any ideas would be very much appreciated. Thanks Dallas.