Xbox 360 - Clear the cache with the new update

Y, X, X, LB, RB, X, X

Or is it "up up down down left right left right B A Start"?

If you refuse to click links, go the System Blade and the Memory section. Highlight the Hard Drive or Memory Unit, and do the above code (not the Konami one, silly!).

Warning: Deletes all game updates. I'm not responsible for any result of using the above information.

That's actually somewhat of a fun way to access a maintenance feature. It really solidifies the gaming-console feel. I'm not having any problems, so I don't need to try it out, but if you are having problems, the option is there.