ok, i made a post a while ago about my friends subwoofers, the bass hits for no reason when the music is off, everyone said it was the rca wires and she still hasnt had time to stop and get some, so she went today and the guy at best buy told her that the subs are about to blow and and that is how u can tell they are going too..i have no idea how to fix/what to fix...anyone know how to fix it?