I have a 2000 GTP with the Bose speaker package. I installed my HU the other day, and things were good. I then tried to install my subwoofer, but even without the ground wire installed, my amp was showing 10v with the car in accessory mode. with the gound hooked up, it would show 12v, and the sub would hum, but no sound reproduction. Then today I was working on the sub, and the stereo cut out suddenly. The HU went blank, and won't power on! I checked all of the fuses, but none were blown that I could tell. The speakers are outputting a slight hissing sound, so I had to unplug the bose amp to stop that. What happened? What can I do to fix this? Thanks,
Harvey

check the fuses under the hood. and then make sure your grounding point is clean and tight.

Ok, the radio is working again, but the sub is still making noise. Could it be the bose amp in the trunk is causing problems? I don't think I grounded the amp poorly, but could it be ground loop interference?

Did you run the wires that run the amp and the RCA wires on the same side of the car?

Cause if you did thats whats causing that noise. Those wires need to be run on opposite sids of the car to stop that noise.

If you did run them on opposite sides then I'm stumped dude.

I got it figured out finally. Like an idiot, I had hooked one RCA into the amp's input, and one into the out-put! It took a while for the amp and radio to co-operate after that, but it's working great now! Thanks for the help!