Ok, here is my setup on my 95 SE. Pionner Headunit, pioneer 6.5in all around. 700s Rockford amp/300watt Kenwood amp, 1.0 RF Farad Cap, two 12" RF DVC subs (HE2), and 4 gauge wire for the ground and power cables. I just installed a tv, but before I did that, whenever I heard my radio, i would hear this faint staticy high pitched noise comming from my mids and highs speakers. Sometimes when I would drive, the high pitched noise would follow the sound of my engine, what I mean by that is, when the RPMs got louder, the high pitched noise got louder and had mroe of a high pitch. Now, I put in a TV, and I hear it through my radio using an FM modulator. The noise is even louder and still is consistent with teh engine RPMs. Also the TV sound is very staticy. Are there certain points on our Maximas where we should ground. Im not ussing the same ground for every wire, I use whatever is closest, Some of them are sanded down. What else can I do? ANy help would be appreciated to get rid of the static or the high pitched noise. It only happens when the radio is on, when everything is off, and I drive, you cant hear anything.

 

This FAQ gives a good checklist on how to debug such noise. rec.audio.car FAQ