What happens if you take a short piece of wire and hold it between the amplifier's ground terminal and its RCA shield while the system is playing and the car is running ?
I just re-read your original post. Do you have a noise filter installed between the amplifier's ground terminal and the negative battery post ? If so, remove it and any other filter installed in your system on the ground side. The system needs a solid connection to ground (meaning: proper gauge of copper wire and nothing else) before any more experimentation is done.
Edited by munkworks (27/08/2002 23:10)
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