Hi, I just installed a 4 channel amp and there is whine through the speakers. The weird thing is when I just connect 2 rca's and 2 speakers instead of 4, there is no whine at all. I also had a 2 channel ampl before, and no whine heard. I dont know what could be the problem, the whine also gets louder when accelerating.

 

I had the whine, I upgraded my RCA's to Stinger and no problems now. Make sure the HU and AMP are grounded in good locations first.

 

Rca's, bad ground. Try the grounds first.

 

I had the same problem, and what everyone says, just fix the grounds, it didnt do it for me. I tried about 4 places for grounding, and still had no luck. I then came to the conclusion it was either my rca cables, or my hi/low converters. The way I tested for myself, was I had a phono to rca cable adapter, hooked up my portable MP3 player to my amp inputs, played it while holding it in the air and revving the engine, no whine. The hi/low converter was the problem at hand. check out the input wires (RCA) for possible problems. and the best ground I found, was putting a hole through the spare-tire well, and bolting it down.