What seems to be the most common cause for speaker interference? Is it a bad ground? Bad RCA wires, Bad preouts? etc.?
I've got some feedback and it's driving me nuts!!!
I'll be replacing the RCA's this coming weekend. Hopefully that will sort it out.
My amps aren't causing the problem either.

Any insight?

 

Bad ground on either head unit or amps. Also alternators without built in IC Regulators can cause system noise