First night with the new MBA...I'm laying in bed with it on my lap, the ceiling fan on, and a baby monitor buzzing in the corner and I can hear a distinct buzzing/humming/whirrling sound coming from my Macbook air. I'm guessing that it's the fan, because I have no idea what else it would be. Can everyone hear their fan noise they clearly? I mean it's certainly not loud, but I can hear it at normal typing distance, with some background noise, and doing nothing but web browsing. Normal? My 2010 MBP is silent.