Dave,
I'm sorry the DMD is cutting out. I hadn't experienced that until we moved it the other day.
Does the DMD still start working after turning the game off and back on? Could that be an indication as to what is going on?
I'm thinking (not that I know much about DMDs) that it must be something loose or a cold solder joint as it was fine until we moved it.
I hope it's an easy fix.