Hi everyone, just had a problem with my MV-50 and wonder if anyone might be able to help? The power switch wont turn off the amp and there is no output signal to the cab or phones output. The Vu meter is still showing input signal. The amp was working fine - I turned it off (so i thought) - came back after an hour to play and had no sound - tried to turn it on and off again and it wouldnt switch off - tried unplugging the power cable, but when replugged in the same behavior happens and the amp comes on automatically but with no sound. Any ideas!?