MVS-1s not booting? (super sidekicks tested)

I have 2 MV-1 boards (uknow the huuuge ones) and they've always worked fine but I sold off all my games. So a friend brought over super sidekicks and it would always go to cross hatch and never start the game....I thought the game might be the problem so we threw it in my extra MV-1B and then it booted....

So has anyone heard of a compatibility issue with this game? cause I don't see any reason why both MV-1s would stop working suddenly (the battery is fine and all hardware tests are 100%).

Sounds like the slots might have gotten dirty over time. Give them a good cleaning.