Windows 7 pointer weird

I have an HP dm4 laptop (sig). Occasionally, the touchpad would not respond to taps/pointing gestures (moving a finger around on it basically). The buttons still work though. To make pointing work again, I have to Alt Tab to a diff window. How would I fix this? I have



Synaptics 15.1.6.64

Windows 7 Pro x64



I've tried updating drivers via Device Manager and Windows Update.