Whenever I’m in a game my helmet morphs into another helmet and it looks weird. If you don’t know what I’m talking about just check my fileshare.
If it makes you feel any better, this is a known glitch. I unlocked the Protector DRFT armor for my weapon mastery commendation last weekend, and I also noticed the glitch when playing in matchmaking. I would show you that I have it, but my girlfriend changed my armor (she’s been trying to learn to play Halo recently, which I am very excited about).
Edit: Never-mind; I do have it on. I guess she must have changed it back when I wasn’t looking.
This glitch has been acknowledged by 343 (finally!) in the Halo Support forums under the thread Protector helmet glitch. Luckily, it sounds like they’re going to try to fix it.