I just installed a small amp to give the sound a boost over the exhaust. Not a lot of money so I went for a cheap unique cycle 300w unit. I ran a direct line to the positive with 16 ga. solid copper. The ground is their wire to the frame. Started it up and constant interference. So I thought maybe the power was too small a gauge so I ran a pc of 12ga solid copper, but still the same noise. Did the same for the ground. No luck. Anything else I should be looking at?