The items in the inventory, only when I open it with E, doesn't happen when in chests etc., move up and down, no matter what is in the inventory, I cannot play because of this and I need it to be fixed.

This is a link to show what is happening:
https://www.dropbox.com/s/9dtmc44e72m9u1c/IMG_1025.MOV?dl=0

I would see if an update fixes this, and if not, try changing the betterfps algorithm and see what that does for you.