I've a 30" Apple Cinema Display (A1083 EMC2011) that makes a noise when lowering brightness (low brightness = more noise, full brightness = no noise).
Gently slamming the side of the screen usually makes the noise go away, for a while, but it always comes back sooner or later.
The phenomenon reminds me of the floor lamp in my living room, which also makes a similar (albeit somewhat louder) noise when dimming down the light.
What I'd like to know is: Is this "low brightness" noise present in all 30" Apple Cinema Displays? (In which case I can save myself the time of asking a hardware guy to dismantle it in search of a cure.)
PS! I should mention that I use the screen with a Apple Mini DisplayPort to Dual-Link DVI-adapter. I don't know if this would contribute to the problem.