Easy solution : I got the same issue with my magic mouse 2. scroll works well but curson moving like drunken guy. when i saw the bottom of the mouse the lazer light is also clear. but i just took a small tissue and wiped those bulbs to make sure. then its started working nicely , then i found the reason that the laser bulbs are covered with some cream or oil, it can be anything , just try wiping the bulb @mouse bottom using some tissue paper , it should work.