I have an Asus LED-LCD TN Monitor, and for some reason, sometimes the screen makes a high pitched noise. The strange part is that it only occurs when some documents are open, and only when they're on certain parts of the screen. Speakers are all off (including the ones in the monitor), connection is DVI, no audio is connected to the monitor, changing brightness doesn't affect it. It's not really a big problem, I'm just wondering if it could be part of a larger issue. Thanks in advance for any assistance!