Jump then crouch in air? Worth a shot. It is the level where you first encounter the flood. I'm at the point where you have to jump onto that block with the dead marines on it, then up to the second level (there's only one with dead marines on it, the others are all dead Covenant). The first jump is easy, the second I haven't made yet.
Having played about 90% of the way through Metroid Prime, that was a really well done FPS. I haven't had any issues at all with the camera in Halo, either, as you have REALLY fine control of it and while strafing isn't quite as easy as with a mouse and keyboard, it's not that hard. You actually have better control in Halo because both sticks are analog, whereas with the keyboard/mouse combo, only one is analog. That gives you finer control but it's much harder to do perfectly.
Man, wish they had wireless mice when I spent all my time on PC FPS. I used to get my mouse cord caught up in crap all the time.