On startup, the DMD on my Viper Night Drivin' game sometimes stays black or the display is all garbled. It always "corrects" itself after 10 secs or so and works fine (displaying high scores, the graphics, etc and works fine during game play), but any ideas on what would cause the issues on initial powering up?

Thank you! All connections were tight, but I unplugged all of them and blew them out and reconnected them. I've played it 5 or 6x since then and it seems to be working again.