I put an MTX MXA4004 amp to run all four speakers in the car and I'm picking up a high volume type noise through the speakers at low volume. I've turned the gains way down and I still have the noise. I'm using the factory speaker outputs for the audio through the high-level in on the amp. I'm not picking up any engine noise or popping so I don't think it would be a ground and not picking up any noise though the deck (like popping while changing CD's or stations).

I've changed the amp and the problem is still there. When the volume is at zero there is no noise but when it goes to 1 or 2 and you can barely hear the music is when you can really hear the noise.

I need help [img]graemlins/freak.gif[/img]

 

Double Check your grounds. And if you think that they are good use your meter and check the resistance of were u are grounded to that of the battery

 

Does anyone know if there is a factory amp in there? If so where is it?