vodkatonic

I've noticed this for several games now that I knew really didn't have any issues running otherwise, but if I launch a game (tried with Galaga, Time Pilot, Mouse Trap, etc, all MAME) from the discovery center they all played with a very obvious lag, almost like it was skipping frames, very choppy video. If I exit the discovery center and then launch the very same game directly from the platform view, no such performance issues appear. Is there anything I can try to resolve this? For the time being, I'm using the discovery center as a suggestion, then I go find the game in whatever platform and launch it there, but that's kind of a pain.