I have 2 mtx 10's a power acoustic amp and a scosche capacitor. When I trun my car off the subs continue to thump at a low volume. When I unplug the rca's the subs quit, but the power light on the amp stays on, it is not from the cap because it is turned completely off. When I start the car up, I can hear the rpm's throught the subs, and it is not the rca's crossed over the power wire because I double checked my wiring. My deck is connected directly to the battery and not the ignition. Please help, make it stop. I am afraid I am going to drain my battery.

well first your amp wont turn off if the remote line is from your deck because you say your deck is not connected to ign. secongly what your hearing with the rpm noise is called alternator whine, somewhere along your RCA path your picking up interferance, could also be from a bad ground, my suggestion, re route your RCA's and properly connect your deck and your problem should be fixed. if not, find a new ground point and make sure you sand off the paint and get a good contact

Wheres your amp grounded? did you sand of the paint?

yup, the amp isn't shutting off so it's still taking whatever signal is going through the RCAs and sending it into the subs. Since the RCAs are grounding somewhere, you're getting a ground loop which makes a thumping sound in subs.

thanks for all the help. Problem fixed!

So what was the solution?