Audio Systems: Amp and speaker noise, rca cables, channel amp

Question
Hello i own a 1994 mk3 vw golf driver, got a jvc head unit and 6x9's and a 600 wat 4 channel amp. My prob is this i have run the power cable down the left side of the car and all the other cables down the right, the system sounds fine till i start the engine then i get an annoying high pitched screech through the speakers, i think it's from the alternator but im not sure can you help me thanks.

Answer
More likely it's where your ground cable is attached that is the cause. Running the cables down separate sides is the way to go. Your ground should be on a clean metal part of the frame or body. Different ground spots cause different problems. Also make sure your RCA cables are away from any noise sources. If your alternator was dying, your lights would be dimming out. The headunit ground van be another thing to try different places.