Interesting problem on my C330

A couple of days ago, I touched my favorites to locate a stop. When I touched the button on the screen, the button to the immediate right activated and it went to that screen. It did this several times,and I finally tried a reset. This cleared the problem...........for awhile. A couple of hours later, the problem re-occured. Is this a common problem with the touchscreens? Is there some way to re-calibrate, or will I have to do a reset each time? Thanks everyone!