A picture might help. Here is a screenshot of the Incident 2's flight playback (what a fantastic feature by the way). You can see that there is no stick input, and it is flying at 24.6mph in a large circle. The playback shows that the aircraft was pointed backward, but actually it wasn't -- it was pointing forward. Where the path curves to the left again and goes off the bottom of the image is where I retook control and flew it back to base. During the rest of the flight playback, again the data shows the orientation was backward, but it wasn't -- camera and aircraft were facing forward. This error occurred midway through the flight and is when I noticed the horizon had tilted -- the first minute or so has the orientation correct.
As far as Mod values, the compass had Mod 1475 after I controllably crashed it in Incident 2 before I powered it off. It had 1527 after doing a recalibration, and 1480 just before takeoff on Incident 3. Interestingly though, the compass X value was -500 to -600 adjacent to both incidents, but +479 on the middle flight that had no problem. I will monitor that value in the future to determine if it's relevant.