Zoom in / zoom out affects bone orientation.

I am puzzled by the fact that when zooming in or zooming out, the bones in my armature change their orientation.

I am using rotate constraints, but why would zooming in or out affect this. Also when I move the 3d cursor, the orietation of the bones swing again.

If I zoom in gradually, then the bones with rotate contraints turn a full 360 degrees and continue to do so.

I have no bones selected when this happens and it happens in pose mode, and object mode but not in edit mode.

???

Ok, just to answer my own question: It appears that there were illegal constraints in the armature setup.

Particularly the rotate constraint doesnt appear to be able to be applied from one bone to the next in the same armature.

Cheers