My MacBook is in for repair, again. However, I've spoken with Apple and they've told me that they're going to replace it when it gets back from the repair center. Anyway, what I'm wondering is if Apple has fixed their MacBooks so that they don't make a high-pitched buzzing sound anymore. That's why I'm asking you, MacRumors forum visitors, how your MacBooks are. The sound should come from under the top left side of the keyboard, and disappear (or at least quiet down a bit) when CPU activity goes up or if you turn off the second CPU core. It also seems to be quite a bit louder when the power cord is plugged in. So, the simplest way to test your MacBook (preferably C2D) would probably be to plug it in, close any CPU intense applications, put your ear next to the top left side of the keyboard and launch PhotoBooth. Any difference? You could also try QuietMBP, or install Apple's CHUD Tools and turn off the second core. I realize not everyone is bothered by this noise, and some might not even hear it when they're using their computer to do regular work. That's why I'm asking you to put your ear next to the MacBook and listen, because it really annoys me when I'm working someplace quiet. I really hope Apple have fixed this, since they did fix it for the MBP (kbase article). So, how does your MacBook sound?