I need to talk to a real live person over at MARSHALL AMPS about my DSL401... How would I get in touch with them? I can't find any phone number for them anywhere on line. What I need is a replacement for that little plug-in channel switching board (the one with the two little black switches) I had it over at GC for over 2 months and their repair guy just jack-legged a "band-aid" type of repair. The amp is only a few months old. I need help!!!