My 2009 ML63 with Harmon Kardon sounds like crap. To me it sounds like an old AM radio for some reason. The sound seems to be mainly coming form the center speaker. The door speakers and roof have sound but very low. The sub makes noise but not nearly enough. You can turn up the sound all the way and it is about half sound and sounds like an old AM radio or an antenna is disconnected. Same sound issue from CD and even the cell phone sound through the radio. Mercedes is telling me the amplifier is bad but I am questioning my dear old Mercedes dealer...they said "they think". Also when you use the balance and fade function it is not balancing or fading to the correct speakers. Anyone have any ideas? Also, where the heck is my amplifier even at in this car. I appreciate any feedback I can get as this is frustrating.

 

Hi mate, it might be an idea to move to w164 section as its specifically for your model amg.