Tap to Click

For some reason, every once in awhile, my trackpad no longer lets you tap to click... Everytime it happens, I have to go into sys prefs and unclick and reclick the tap to click selection. Does anybody know why this happens and if there is a permanent fix??

It occurs at random moments and I can't reproduce it. Any help would be greatly appreciated!!

Have you tried calling Apple? I had a problem with my clock not refreshing the time and I would have to open "Date and Time Preferences" and when I opened the window the clock would correct itself. I called Apple and the tech walked me through moving, removing, replacing some Preference files and Cache files. Maybe they can do the same for you. Good luck.