I received my MacBook Pro (2GHz) on Wednesday. I had read about the hissing noise and sure enough shortly after unpacking and playing with the machine I noticed it as well. Ah well, I thought, let's give it a run to see the performance before I send it back.

I was compiling code while loading up World of Warcraft (believe it or not, I had 30+ fps while compiling mysql...) and spent a whole evening putting load on the machine. Very much later (after WoW and the TV were off again) I suddenly noticed that the hissing noise was gone!

Previously, the only way to get rid of it was dimming the display until it was off. I'm not sure which category of hissing that falls in but at least in my case it seems like some "burning in" of the machine got rid of it. (Yeah, I know how unrealistic that sounds, but what are the chances my hearing degraded that same night ;))

I am *very* happy with the machine's performance and they'll have to pry it from my dead cold fingers if they want it back ;)

Sven