I really enjoyed the campaign of this game, fantastic (despite a few blips in the flow of the story telling).
One thing that really bothered me however was those sounds in the cutscenes. Mostly explosions/background noises that sounded like absolute CRAP. Example:
They sounded like they were compressed to hell, almost like they were free wav clips they found online.
Maybe it was for performance/disk space reasons......but it really killed the immersion for me, since the audio in Halo has always been absolutely top notch.
