[nass]

check your ground make sure it's a proper ground, make sure the ground cable is atleast the same gauge your power is and make sure it is under 18"

for your RCA's check the back of your deck make sure they're all plugged in. Your deck might have a sub output too maybe one pair got plugged into there. The might be a break in the RCA I would double check that the RCAs are indeed fine. Umm what else some amps have RCAs for input and for output... gains? double check each amp actually turns on could be that bad ground that's causing it.

that's a few things off the top of my head letme know if anything helped