Car Stereos: Subwoofer problems, rca cables, audio signals

Question
Alright so I'm just going to tell you all the problems that I've encountered.

I am running a 12' Memphis M3 (rms 500/1000w) with a Pioneer 760w amp. This with a kenwood head unit.

Well I had recently broken in the M3 and now it plays fine. I still have all my settings at 0 levels from the break in period. Gain is about a little past half and bass boost is all the way up. While driving down the road with the deck turned OFF. I will hear the subwoofer playing bass, as if matching the engine noise of the vehicle. When my rpm's drop, the bass gets louder, and the opposite when rpm's are raised. I have been trying to pin point this problem for some time now. I can't see it being anything at the moment, ground is nice and secure, and on a good surface. power wire is free of obstructions, rca cables and remote wire are ran in a seperate location from the power wire.

Nothing that I've done can seem to fix this problem, other than turning the gain down. This happens if the deck is on or off, i'm thinking it could be the remote wire? I have it spliced into a wire that turns on with the ignition, but that shouldn't be giving off any audio signals.

Also with the settings still the same, when I get to a certain volume the sub will distort and cut bass out here and there, and ultamatly cut my sub off completly. I've blown both fuses in my amp because of it.

If you could help at all I would extremely appreciate it.

Answer
Jerry,  Sounds like a strange problem.  What does it do, when the engine is off?  I would start by checking the voltage coming into the amp when the engine is idling and when it is being revved.  If the voltage is the same, then there is no engine related problem that is causing your problem.  The rpm based noise problem that you are having is an open ground circuit.  This can be from different sources in your car.  If the source is far enough away from the battery, it will always affect your sound system.  If the voltage changes with the rpms, then you need to repair the car's charging system.  If it is an open circuit, there are a few tricks to try and eliminate (or isolate) the noise from your sound system.  You have checked the ground wire.  Is it connected to the nearest possible point, and is the gauge of wire as large as or larger than the power cable?  The ground needs to be a large wire and needs to be connected to ground as close to the amp as possible.  The other fix is a line conditioner that you can wire into your power wire.  It is a simple little box that filters the incoming power to get rid of outside noises, but it will not completely solve the problem without fixing the other problems.  Hope this helps, Scott