I have an Alpine 12 inch E class, a Sony Xplod 1000 watt 2 channel amp and a Pioneer head unit. So yesterday I was hearing alternator whine and ignition noise from my sub, so I started checking it out. After the tests I did and, I found that my amp is being powered and grounded correctly, the RCA plugins on the amp are being powered, but not grounded to the amp ground. So I put my sub back in today (I had taken it out when I did the tests) and now either the amp isnt working or the sub isnt working. I checked the signal wire and its not grounding to the amp ground now either. So now my car is taken apart, and I have no idea what to do.