I had the same issue. The screen was very jittery and holding by the corners of the devices would send random keystrokes. I was sure it was a hardware issue, until I noticed that the issue always happened during or after playing Sudoku Challenge. I uninstalled a lot of start-up programs and have been limiting the number of open programs - the issue hasn't happened yet today. It could be a coincidence and there is a loose connection somewhere or it could be software incompatibilities...Not much help, but I wanted to let you know you aren't the only one.