I had been noticing that some of the buttons in NewsFire weren't working. Upon further examination, I realized that I have a 2" x 3" area where the mouse is not detected. It happens in all apps, including the menu bar. The area begins at the top of the screen from a point perpendicular to the right edge of the black apple logo. Is there some component behind the screen that could be causing this? The iMac is covered under AppleCare.