See if he has the auto lock if doors aren't opened turned on (I forget the exact name). It is where the doors will re-lock if not opened within 30 seconds. If that is on, and he is accidentally pushing the unlock button (it can happen, especially when wearing jeans), then the windows would open, along with the sunroof, and since the doors were not unlocked, they would re-lock 30 seconds later.
So...
Turn off that option (under door locks I think in settings), and if he finds that his windows are open and the sunroof is open AND the doors are unlocked, then well, he is either pressing the key or his car is possessed.