FR-4x, FR-4xb: The bellows exhibits an erratic behavior.

If the bellows doesn’t work as expected, causing notes to sound even while it is not moved, its
sensors may need resetting. To do this, follow these steps:

1. Switch off the FR-4x/4xb.
2. Close the bellows by pressing the air button.
   Note: Be sure to completely close the bellows in order to purge all air. Close and fasten the bellows straps.
3. Stand the FR-4x/4xb up on its back feet on a flat surface.
4. Press and hold the [◄] and [►] buttons while switching the FR-4x/4xb back on.
   Note: After a few seconds, the display shows “Complete CALB” and then returns to the main page.
5. Switch off and switch on the FR-4x.