Fwiw, I was using facetrackNoIR with freetrack and clip on IR lights...and my view did the same thing, sudden jumping and extreme angle changes (e.g., a 30^ head turn to left = -90^ pitch + 30^ roll).
A comment on these forums suggested using opentrack instead of FTNoIR, and this reduced the craziness but didn’t make it go fully away.
I’ve adjusted anything the seemed to help with this, but no go. I’m wondering—because it came upon me suddenly, no lighting change, background conflict, etc—if there was an update recently which caused a problem.
Or maybe the IR leds are just dim? (If I shorten the distance to the camera it seems to work better)