iLO XM-MP3-CD Car Stereo "wiring gauges boat" Questions

...boat. I replaced all 4 existing stock speakers with new Polk audio speakers. After wiring the head unit, everything is fine and operational except when I turn the stereo up it does not distort as ...

...boat person). Ground for the radio needs to be either through the chassis (any existing screw or mounting stud on the radio will do) or via the manufacturers installed wire. That takes care of the ...