BI has dodged this TrackIR issue for over 4 months now. There are various scenarios that make this bug occur but in general all involve a camera angle value that differs from your TrackIR centered view value.

Whats Fixed?  The value in question is "zeroed" when feet hit the ground after exiting a vehicle and standing from prone.

With the exception of weapon inspection, full time Mouse Freelook, which is looking around with the mouse even when ALT is not pressed, has been disabled. ALT can still be used to Freelook if needed. Release of ALT Freelook recenters Freelook to match TrackIR view, so the next time you press ALT, or go to build, repair, refuel, vault, climb a latter, etc.. your view is not SNAPPED to a stale Freelook view.

TrackIR Freelook Conflict Fix

Fixes conflict between TrackIR and Freelook.

TrackIR Freelook Conflict Fix

1.0.119

1.0.118