Hi People, I am going to be installing a Sony XAV-601BT soon. My car is a 2004 A3 with full BOSE. I have the PC9-408 adaptor and just wanted to ask if it's just a straight plug and play? Been trying to google the question but find lot's of different answers about swapping wires over etc. Considering the last time I changed a stereo in a car was about 25 years ago, I am getting a little confused! Also on the adaptor there is a red lead that says it needs to go to the ignition 12v. Does this need to be used or is the ignition already incorporated into the Audi harnes? Here is a picture of the harness. The lead is this (Not from Halfruads) Halfords | Autoleads PC9-408 Audi Bose Active Adaptor With This: Line Output Converters | Autoleads Many thanks in advance, Simon.