Contour Enthusiasts Group Archives Forums Modifications Audio Whistling noise through speakers

Hey,
I have a clarion drx 7575z headunit with pioneer 6x8 speakers and a profile clarus series amp (50w x 4 RMS) mounted in my trunk. I did the installation my self to make sure it came out clean no idiot at curcuit city busted anything. My power cable runs along the drivers side and the patch cords run along the passenger side. Everything is underneath the plastic kick panel inside. My ground is good but i still get a whistling noise through the speakers that gets louder in pitch as the RPMs go up. It also gets louder when I turn the A/C on. I tried these magnet noise reducer things that clamp over the cable on both the patch cords and power cable. This did nothing. There is a lot of space between them though so maybe they are too big for the wires?
Any suggestions on how to eliminate this noise?
Thanks
Steve

My 1999 Contour SE Sport 2.5L ATX did the same thing, the speakers whistled, and it got worse the faster I went, or if I turned on the air. I did not have an aftermarket HU or speakers. Turns out that when I took the car in because it wouldn't start, the dealer found a lose ground under the dash, and when they tightned it up my whistling went away. Even if you didn't take apart your dash, look for a lose ground anywhere near you HU, speakers or Amp, cause a loose ground can cause interference. My car's wire was lose because the dealer forgot to tighten it after a service. However I found another wire in the trunk that was a little loose, and the dealer never did any work there. So like I said check the grounds.

yea ground cable is what im thinking too, something isnt grounded right im guessing.....

Well, I guess I have some searching for a loose ground somewhere. I also have to get the cd out that is stuck inside for some reason. I dont have any clarion dealers in the area and Tweeter wont do it bc they dont sell clarion. Hopefully I can take the housing off and see whats jammed.
Later
Steve