There is probably another thread on how to fix this problem but i couldn't find it. After i got my sub installed in my car by "Strathfield" (never going there again) i didn't notice untill i got home that there is some interference coming through the speakers from the engine? Its been a month since it was installed so i think its a bit to late to take it back and get them to fix it. I kept forgetting to take it back :doubt: . How can this be fixed without having to change wiring or whateva? I have no idea when it comes to car audio and i don't wanna attempt to fix it myself?

Altenator whine.

Relocate ur speaker rca's away from electrical cables. Dont even let them cross each other.
Ensure the ground on your amps is short and properly mounted (sand back ground point.)

Can be millions of other reasons for ground loop/ interference but this should help you out.

Search for altenator whine... been done to death

Narrow it down - Try plugging in an ipod to ur amps directly. If the sound goes away it is RCA's or headunit. If its still there it is the amp.

Change your condenser on the coil, cheap as, simple 2 do. :D

Sounds slightly excessive... ;)