I have also tried all the, what seems stupid, ideas. Laying the whole contraption out flat, nothing. Connect in stand by, or with screen on, nothing. Different angles, nothing. Connected it on my desk, my couch, my footstool, nothing. Tried not looking at it while I typed, with positive thoughts, nothing.
I have also tried with my pencil on and off, nothing. As above, left my pencil in one room and went to another, nothing.
I did go to Baskin Robbins today and it worked while I waited on a milk shake. Not joking, it really did start working.