tried to have my amp and speakers installed today but the installer gave me some bad news said none of my preamps were any good said when hooked up the were crazy static coming from speakers. tried to trouuble shoot several diffrent ways but to no avail then finally stuck in new head unit and no loud noise or static. has anyone else had any problems with there preamps if so can anyone give me an idea.

I've seen it happen once or twice in the past. Though it's normally been because someone screwed up a connection and it back fed into the radio.