somtimes when you pause the game and then quit to title the game does not correctly save your position. If you are underground at the moment of pause and quit, you will sometime be returned to a location somewhere above where you were. This happens very often. This may be related to finding doors open that were closed befor you paused and exited to title and then found them open when the game was restarted. This may all be related to what is saved at the time the game is paused.