Like many others, my VR920 has encountered tracking issues since I took it out of the box, especially yaw.  Even performing calibration after calibration, the result was only marginally improved in most cases.  After seeing another thread that discussed PSU and monitor interference, I calibrated my HMD and then moved it around my desk, close to the monitor (21" LCD Widescreen), near my desktop speakers (Cambridge Soundworks 5.1), and back and forth over my mid-tower unit, which sits just to the left and forward of my left knee.  All this with no effect upon the tracking indicators in the Calibration and iMonitor windows.

Last night, I happened to have my Calibrator window still up when settling in for some FSX attempts with the VR920 (still having some issues), the HSD already secured to my head and receiving signal, and put my headset on.  Wow, did my tracking jump!  After reading all the explanations of modern speaker electronics and how they shouldn't affect tracking, especially ones designed for computer use, I was surprised to see how much they DID affect it.  Moving the headset forward and backward on my head caused the yaw to vary considerably (+- 30) and my pitch and roll just slightly (+- 5).  Once the headset was placed in position, my tracking appeared very close to my zero setpoint, however, turning my head and looking around caused erratic yaw and even a noticeable drift.  To further test this, I went into FSX without the headset on and my tracking was improved considerably.  Two issues still remain (forward-look is skewed about 20 degrees left and considerable "vibration" in image when looking down at instruments), but the sensors followed my head movements much more smoothly than before and with no drift.

Not sure what I'm going to do about this because I'm doing all I can to give the VR920 a fighting chance to impress me, but this headset is by far the best one I've ever owned in terms of comfort and sound (Plantronics Gamecom).

"Living life one humorous day at a time."