I just got my Soldano Decatone and it makes a fizzy noise when passing signal. I hope you guys can hold off on the fizzy Soldano jokes long enough to hear me out. Even on the clean channel, the amp makes a hissing/fizzing sound, but only when it's passing signal. When idling (not playing or guitar volume turned down) it's dead quiet. I've tried swapping out preamp tubes and pulling duets but with no joy. I'd just as soon not have to ship a brand new amp back to the Manufacturer for service. Help (and thanks)!!!