I am having a similar problem that just developed today, going from bad to really bad in one day. Now if I touch any part of the screen or the silk screen buttons below the Palm reacts by displaying the dropdown menu in the upper left. The next time I touch any part of the screen the menu disappears. I had recalibrated the screen with the digitizer earlier today when I started getting inconsistent responses to tapping. It made no difference. Is there a place on the Palm where pressing or knocking might reset some loose connection that is causing the problem???