Before performing the reset, we would always recommend that you backup your device's settings via a Sysex Dump. Steps on how to do this can be found at the following link;
With the Deepmind off, Push and hold the "PROG" and "WRITE" buttons beneath the display and power on. This will then put the Deepmind into it's bootmode.
From here you can reset various parameters back to their factory state or completely re-initialize the device by using the "RESET ALL" option.