For those with a new HD PB G4 15".... Sit in a quiet room. Load up a long web page. Use the keyboard arrows to scroll all the way up, then all the way down. Do it a couple times. Hear that sound? Load a page that has a flash object in a web browser. Hear that sound? Put your ear close to the keyboard and use the trackpad a bit. It's more faint, but do you hear a sound? Set your dock to auto-hide. Listen closely and use the trackpad to hide/unhide the dock. Hear that sound? I just farted. Hear that sound? None of these sounds are good. I wonder if anyone else has these problems (the powerbook problem, not the gastric one).