So i got my first 24inch imac from Amazon and it had the brightness related hum that was also effected by the angle of the monitor and it was really annoying. I got apple to exchange that for a new one. The new one also had a brightness related buzz. Not as bad but it never went away even on max brightness it just got lesser so now i got them to take this one back. I'm so sick of all the hassles with this damn machine, now im waiting for my third one... Does anyone not have horror stories with this machine? I'd like to know some exist without the electrical hum so im not just settin myself up for another fall