hello! i have a moog voyager, purchased last year. while playing with my band last night everything was fine. then i went back to play the moog again and got no sound. i checked all of the obvious in/out problems and turned theunit on and off again. then i unplugged my headphones and wham! the problem: when the headphones are not plugged in, the master volume knob doesnt work yet the output sound is at 100%. when i plug in the headphones, the master sound and the headphone sound go to 0%. also the “keyboard on” switch seem to be turned on. if you know how to fix this please help!!! i have a show to play tomorrow!! thank! 