Every time I touch my touchpad (which usually acts as a mouse) on my Surface Pro 3, my screen turns off. It doesn't shut down the whole tablet, it basically just locks it. The mouse icon might move slightly with my finger, but after about a second my screen goes black. I can touch a key on the keyboard to turn the screen back on, and log back in, but if I use my touchpad again the same error happens. So my keys work fine, but my touchpad does not.