I noticed this happening around half way in act 2 but it seems that if your party is moving and you're moving the camera at the same time the camera hitches.(some sort of camera stutter?)
My main is a Paladin and I started to notice it around act 2.It's around the time I applied my aura.Apparently you need to apply the aura for it to be permanent and it fits at around the time I started to notice the issue.
It seems that when I move around my companions lose and keep re-applying the aura buff as soon as they get closer to my character which causes the camera hitches.
I just respecced my paladin and this time I didn't apply the permanent aura and its much smoother when panning around.