Doyou get sound out of the unit with any other preset, which doesn't use the preamp?
Which OS version is the unit running on?
Let's try this sequence:
-Load preset #1810 Arkham Distortion
-press the [preamp] softkey four times
-now you should read:
mode: assign 1
Please report if that's what you see in this pedal setup page.
All the best