High pitched noises from LCD (when turned off)

Hi,

I have a brand new Dell E228WFP that seems to be making a high pitched squeal when it is off but still plugged in. The sound is quiet and unobvious at first, but after leaving the screen off for a while it gets loud enough to be irritating.

When I put my computer into Sleep mode (Windows Vista) just now, I was able to immediately reproduce the louder noise, and it's still very annoying. The noise happens when the LCD is in standby mode (orange light) and when off.

Furthermore, when the monitor is on (and showing an image), putting my head over the screen I can hear a buzzing sound, much like the sound of a dying CRT we once had at work.

Is something wrong with my LCD's power supply or something? It's supposed to be brand new, but for some reason Dell included an obviously used/old DVI cable and made it look like they shoved in the manuals/documentation as an afterthought. The screen looks fine, aside from a presumably normal brown hue.

Thank you!