That's tricky, especially in the case of something like BIT.TRIP RUNNER. As much as I enjoy the sounds in those games, I'm inclined to say that they wouldn't be allowed. Despite the fact that they're not "songs", per se, the randomness of the notes and obstacles doesn't really differentiate well enough between options to avoid nearly reproducing a usable piece from the soundtrack. I'm open to other opinions on this though.
And that being said, the individual sound effects themselves should be fine - just not the arranged pieces.
And that being said, the individual sound effects themselves should be fine - just not the arranged pieces.