When I go on to my singleplayer world in the pre-release, my mouse goes all crazy by exaggerating any move I try to make. For example, when I try to look to the right, and just push my mouse slightly to the right, the view swings like 90 degrees to the right, way farther than I told it to, as if I've set my sensitivity to HYPERSPEED, but it is only at 100. It does this inconsistently but very often, so I never know when to expect it, and it is very frustrating because every time I try to move, it swings into a different direction, making it almost impossible to play. It is worse when the game is loading new chunks or I am moving fast. I've only noticed this in the pre-release to 1.9, and not in 1.8.9. I tried to fix it by changing my sensitivity to yawn, but it still would swing way farther than it should when I try to move my mouse, even though it was less than when sensitivity was 100 (because of the lower sensitivity).

I'm not sure how you could simulate this problem if it hasn't been noticed by anyone yet. I don't know if I'm unique in this problem, but it is a pretty serious problem for me and I don't know if I can play survival through it. If you need any more information, I'll be happy to try to supply it, I've tried my best to describe the bug without being able to show you. Thank you!