I have a 500k Cap from walmart and It worked fine with my Kenwood KAC-7204 Amp. The other day I bought a Rockford Fosgate R500-1 amp and hooked it up and turned on my amp it goes from 12 to zero and wont let the amp turn on and majorly drains my battery. . When I take the capacitor out and run the just the amp it works fine and doesn't drain my battery at all.. What causes this and what do I do? I don't wanna buy a new cap if the amps the thing messing it up.