My 2011 F350 has the upgraded audio system and I was driving with the tunes cranked all of a sudden the drivers side front door speakers cut out and I have tested the speakers and they are fine I don't know what is the best way to test the amplifer, the other thing I have noticed is now when I shut off the truck there is a kind of pop noise coming from the subwoofer. Anyone have an Idea what I should do or should I just take it in. The only thing that I could think is that I fried a channel on the amp.

 

If you're still under warranty, might as well let Ford do it. It sounds like maybe a bad ground has presented itself.