Ok, I have just installed two Kicker amps(120 & 240) into my Honda Accord. The 240 powering the sub works perfectly fine. The 120 is running my 4 speakers. The HU is an Alpine 7875. The problem I'm having is there is noise coming through the speakers with the engine on, I have unplugged both sides of the RCAs(HU & amp)and it stops both times. The ground is clean. Sound is clear when car is off or alternator is off. I've checked and rechecked connections and I can't find a problem. Other problem is when I turn the volume up... past 7, the speakers pop and turn off, but comes back on after a few seconds but pops again unless I turn it down. Also, the speakers pop when the amps turn on. Anyone have a solution to this mess?