terrytre :
I had this problem but I changed the "cursor shows while typing" and it has not occurred again.
You are hiding the issue not fixing it. It jumps around in 95% of cases because you are on a laptop with a touchpad and your palms or something hits the touchpad, then you see the cursor move. Only thin you do by hiding the cursor while you are typing is that you no longer see the cursor move.
It's like saying "I was bleeding from my arm, but I closed my eyes and now can't see any blood so I'm OK now".