My Xbox 360 Elite started making much more noise now, I mean in every game I play(even Halo 4, WATCH_DOGS,Black Ops...newer and older titles). Much louder. Usually it would do this for like 10 minutes and then diminish a little, but it keeps on going loud, even after I quit the game and enter the dashboard (when opening the xbox 1st time in the dashboard it's silent). It's not the optical drive, but the fans(I think). They're not clogged with dust (I keep it in a clean place).
Could someone help me figure it out what's going on?
P.S:Out of warranty.
EDIT: Now when 1st time opening the dashboard it's silent, when opening up the game for 10 minutes it's loud (as if it installing the game), and after that it's silent.BUT it get progressively louder until it's annoying. I'm getting used a bit to it now but I'm worried about the console overheating or something if I play for longer on it (~3-5 hours) especially when playing with friends.
The console's PERFORMANCE is NOT REDUCED in any way though. EDIT #2:
Halo Reach is a bit lagging (I played a lot before) and this didn't happen. Could be the shitty optimization?