I Tried twice and it happened both the time, so I can't say that it happens always, but certainly sometimes... I will test it further to watch reproducibility.

Problem: When playing in 3D on a 3D TV and you stand under a tree after running a bit around the game sort of freezes... I can hear the nature like birds or walking players around, but I cant move anymore. The mouse does not react to movements or clicks, and I can't walk or open the Inventar, even the Esc Menu does not open, so I can't leave the game.

ALT + TAB works and brings me back to the desktop where everything is fine, I have to close the Game and start again.

had this issue only when playing 3D.