In a 2008 BMW 335, I have the LOC wired and a JL 500/1. I have 3 different sets of RCA cables so I know they ALL can't be bad. When i plug them into the LOC and run them to the amp, the sub barely moves. But when I take one of the RCA cables out and touch it to the outside of where it plugs in, the sub then hits like normal. What could be causing this problem? Bad RCA inputs on the amp I am thinking? If so, how would I go about repairing them?