I just turned my Mopho x4 on after a few months of disuse (not stored曜ust sitting in a home studio bedroom not being played). No sound comes out. Also, the patch-name doesn't change as I turn the pots through the various patches/banks (i.e., the patch-number and bank-number are changing on the display, but the display's patch-name remains unchanged).
I disconnected all cables耀till no sound even through headphones. Any ideas? Recent firmware installed; performed several hard power-cycles, keyboard = "on," etc. . . .