>>396356265
Mine used to be rock solid, but after a factory reset I have to recalibrate constantly. 

I stuck a tracker on the actual headset in hopes of using bd_'s Continuous Calibration fork of Space Calibrator, but it seems to give me correct but offset results ( off by distance between the two reference trackers? ).

Even if continuous calibration doesn't quite work yet, with a tracker attached to the headset, recalibrating only takes a moment, and the same fork as the reuse-samples thing so calibration time is cut in half.