solution found... run front speakers off of the head unit... to heck with the amp expcept... only use it on the sub... what a waste. ive gone through everything... tried ground loop isolator (helped but no cigar) and talked to an experienced tech who says more than likely it is just the fosgate amp being noisy. disappointing to be sure because i grew up with fosgate and they kicked butt... guess all good things have to come to an end.