Another Engine Noise Stereo problem...

So I'm back to trying to eliminate engine noise from my in boat, tower, and perfect pass beeper/speaker. Last year, I couldn't figure out the problem. I ran new grounds directly to the battery from the HU and EQ. Didn't work. I played my ipod directly to the amps, no noise. I was thinking of running power and ground directly from one of my amps to a relay and using the existing stereo power to close the relay. I would run HU, EQ, and perfect pass to the relay. Would this work? I was also thinking of re-grounding the distribution block....

Thanks!