To restore all setup memories in the RD-500 to their factory default settings, follow the steps below.
- Switch off the unit.
- Switch on the unit while holding down 1 and 8 in the NUMBER (Setup Memory) buttons.
The display responds as follows: - Press the [YES] (DEC) button.
To cancel it, press the [NO] (INC) button.
Owner's Manual: https://www.roland.com/us/support/manual_archive/