I am having the same problem with mine. One other thing I noticed is that the VOA point cloud in the portal seems to not be correctly oriented (I believe it's down and rotated). Once I fix this I plan to conduct more test flights - but with QGC open, when the Starling did as you describe, QGC announced that it had switched to Altitude mode. It apparently did this on its own because I had it just hovering in place in Position flight mode.
S
Shane Goodwin
@Shane Goodwin