In my installation, I have a tiny cheap amp powering the front speakers, and larger expensive amps powering everything else. Although I've reduced my noise problems to my satisfaction (by reducing the amp gains), I'm pretty sure the existing noise problems are all due to ground loops between that cheap little amp and everything else. If I remove that amp from the mixture, all the noise goes away completely.

Yeah, that sounds exactly like my installation. The front amp that drives the front speakers and the roll bar speakers is extremely cheap. The noise isn't really audible from the sub anyway, because its bass only, but I wonder what would happen if I hooked the front speakers to my expensive amp just temporarily to see if it removes the speaker whine... Hmm something to think about.

Thanks,

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