Anyone else have this trackpad issue?

Sometimes when I go to click something my mouse will jump to the bottom left of the screen, which I have set to activate dashboard. This happens about once a day and there seems to be no rhyme or reason to it. I've been paying attention and I only have one finger on the trackpad when this happens and I'm not swiping with my palm or anything else. Even if I purposely mess with the trackpad I can't reproduce the effect. Has anyone heard of this or know what I should do?

I have a 2011 15" btw.

 

I'm pushing it down, I have tap to click disabled.