If you buy a quality head unit, you would not have that noise. The factory ground(black wire) is sufficient. Your problem most likely is within the head unit itself. Boss is not a good brand. I would suggest a unit made by a better company such as Pioneer, Kenwood, or even Sony. If you need a ground, you can run a wire to one of the kick panels where there should be a factory ground point on either side. I've had my head unit hooked up to factory power/ground connections and I've never had a noise
2005 E4 EDGE 182CI of FURY!
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