Quite recently, after working flawlessly since the day one, my HP Reverb head tracking started to drift (resulting in broken immersion and frequent centering).
Googling suggested many solutions (with complete reinstall appearing quite often ) but the first one that seemed logical to me actually worked well:
Yep, have done this a few times! I recommend doing it any time you use your headset in a new location, or change anything (wall decorations, furniture) in your sim area.