I have a 2.4GHz Penryn MBP and whenever I run iTunes visualizer (which is where I first noticed it), play a game, or sometimes even scroll a web page, I get a buzzing sound right underneath the screen in the middle of the keyboard area. Its louder the more intensive the app is for graphics. Someone on the Apple Forums suggested that it could be the video circuit, and it could be oscillation occurring from a coil. My biggest problem is, I installed my own 7200RPM drive. Should I go through all the trouble of re-installing the stock drive before brining it in to my local genius bar? I don't want to have them say, "Ok, here's a new one" and then lose my faster drive. Any advice is appreciated!