SR-20HD: The buttons and knobs aren’t working.
You can disable operation of the panel buttons and knobs on the SR-20HD to prevent unintended operations (Panel Lock function).
Long-press the [MENU] button for at least three seconds while holding down the [VALUE/CURSOR] knob to release the panel lock.
To select what to lock with the Panel Lock function, refer to “Disabling Panel Operations (Panel Lock)” in the SR-20HD Reference Manual.