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1. The amp whines when the radio is on - getting louder as I accelerate. It disappears when the radio is off so it certainly isn't the gearbox (my first thought). Is this normal? The radio has been upgraded and there's a second wire to the positive battery terminal which I'm guessing is for audio bits and pieces.
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The whining sound could be a symptom of a bad earth.
This site has a few pointers:
http://www.crutchfield.com/S-Od4XRjaG5b6...tion_guide.html