Okay Im at the edge of insanity and I honestly cant find the problem here. I have ownded a mesa single rec head, a peavey 5150 and I had given up so I just settled for a bugera 6260 2x12 combo. Through all of these amps I have run a ibanez ts9 and a boss ns2 and once i get the amps to about 4 for volume this feedback comes out of nowhere. It has done it on all the amps and Its driving me crazy. I have tried new patch cables and everything. PLEASE HELP ME!!!!