Yup, same here. It feels like that the camera position (the other 3dof of the 6dof) is limited to certain positions and makes for some unsettling behavior. I've tried changing my TrackIR profiles and even using exclusive mode to make sure it's selected and working, but no dice.
I found a way (a simple one) to solve this sort of problem (TrackIR not zooming enough/limited to certain positions):
1- Go to "Options" and than "Controllers"
2- The aproach axis from TrackIR which is "TrackIR -tZ" is assigned by default to "Head Foward (Anlg.)" -> Unassign this command!
3- Set the "Show:" filter to "All controls"
4- Go to the "Zoom in (Continuous)" command and assign the "TrackIR -tZ" axis to this same command ("Zoom in (Continuous)"). Note that there's NO
need to assign the "Zoom out (Continuous)" command.
5- Save changes
With this the TrackIR zoom will be much more smooth and the player will be able to aproach the instruments panel and thus be able to read much better the instruments.