Hi All, Just got back from the dealers. Car was in to rectify a buzzing speaker (rear right). The buzz is interference that changes with the engine and no audio output at all. The dealers ordered a new bose amp and speaker to be safe, fitted both but the buzz is still there. I know its not the head unit since I have an rns-e which i retrofitted, and re fitting the concert 3 unit gives the same. Any ideas?, the car is back in next week for them to take a closer look but I am stumped and wonder if I did anything in my retrofit?.