For some odd reason, I have been experiencing some creaking when I move the display of my Unibody 15.5" Macbook Pro. At all. It just is very annoying, as it has a distinct plastiky sound to it, and it was not there to begin with. I don't know if this matters, but I have a Speck clear case that I used, but then I took it off because it seemed to be twisting the display a bit. Is this creaking a known issue with the Unibodies, or is it just because of the Speck case? I have never dropped my computer, and it has never been mistreated. It just leads its life on my desk or in my laptop bag. Any ideas?