to perform a factory reset do the following:
- power off OP-1.
- press and hold [com] (upper-right side) while turning OP–1 on.
- press button number  to factory reset your unit.
note: all user data will be removed when preforming a factory reset.
after the unit resets, turn OP–1 off, wait ten seconds and then turn OP-1 back on.
for more information please see the user guide.