94 GT with Mach 460 and cheap Sony HU. This is not RPM related but comes from bumps (driving) and vibrations (radio too loud). I've pulled the driver's kick panel off and messed with the connections there with the radio on and didn't find the problem. I've pulled the HU out and messed with that connection with the radio going. I had the alternator tested (good), replaced the ground strap between the frame and engine, cleaned the contacts from the battery to the engine, replaced the power wire from the battery to the power distribution box. The noise sounds like someone blowing into a microphone. It happens in all speakers, I put the fade to the front, back and in between and it's still there. I'm sure it's a wire shorting/grounding out somewhere but I have no idea where else to look. Does anyone have any ideas? I need the radio to mask the transmission gear whine. Thanks, Dan
Well, damnit, it works. I turned the radio on without starting the car and contortioned myself in the trunk. Wiggled all the wires/connections and it sounded good. There was one bundle of wires that went to the driver’s side amp that was hanging down. I tucked it up like the pass side but everything else seemed good. I drove it home over the worst roads Winnipeg has to offer and no noise. So I guess the problem was in that bundle. I didn't hear anything when I was moving it. Oh well. Thanks for the suggestion, I'll keep an ear on it and hopefully it stays where it's supposed to. Dan
