Had the same problem with my mouse. I tried to rollback to the old firmware, but that only helped slightly. I ended up changing the polling rate of the dongle from 1000 to 500 and that helped out significantly. Seemed like it was registering another click depending on where I was clicking on the left mouse button. Further to the outside seemed to be the worst area for this to occur. Figured that it might be a sensitivity issue and changing the polling rate might help not register the ghost click.
