Today, my display began to get stuck auto-scrolling to the top and to the bottom of whatever I have open, as if my mouse scroll wheel is haunted. The direction will change many times in a split-second, although the mouse pointer will still move as directed. (I know the mouse is the main issue because the keyboard is perfectly responsive when the mouse is unplugged.) Oddly, the problem comes and goes, occasionally giving me a few seconds of correct control. It's a PS/2 ball mouse, dust-free and has taken no visible damage.