I got mine in october '07 (4 months ago)and from the start every time and the only time when it makes this terrible scratching noise like someone's sharpening a blade in a workshop, is when i play Halo 3.
it's sooooo annoying! it doesn't do it when playing Gears of War, CoD4, Burnout paradise or any other game! it's weird
i have a 360 for one year, with continued playing. 2 week ago it started to make strange and loud noises when starting to read a game. My question is...it would be the laser...does it need cleaning or calibration or something?? or it is gonna be dead soon? Or by the other side may be the DVD quality for example scrachted or dirty discs? Thanks.