So here's the setup: I put my gear into my car so I can tinker with it over the holidays, but have run into a problem that's got me stumped... There is a constant low rumble coming out of the only sub I have in, and its visibly bouncing. It stops when I pull out the RCA's from the master or slave amp, and also stops when I drop the gain to near nothing or drop the LPF to like 30 hz, but I'm pretty sure that's just a result of the amp's doing what they're supposed to do...

Another thing I've noticed is that noises from the deck (a kenwood deck that's a couple years old) are transmitted to the subwoofer as well. The sound of the disc being read is played, there's a thump when I skip tracks, and even when I tap on the side of the deck there's a loud thump.

I first thought it could be RCA's, but now I fear that I'll need a new deck, or something with the amps is wrong.... Any ideas?