OK, I know the subject has been 'beaten' to death but I can seem to find the answer that I am looking for. I have a '99 c280 with a Audio 30 with the Bose system. I want to put an aftermarket HU and integrate it with the Bose system. It seems like pre-99 model, the consensus is that you need a line converter between the aftermarket HU and the Bose system. For 99 and later model, it seems like I don't need a line converter. I talked to a Becker tech over the phone but he didn't know what type of signal coming out of the Becker HU going to the Bose. Anybody knows for sure which way shoudl I hook up the aftermarket HU, line converter or not. Remember this is on a 99 C280. Thanks a lot.