I've seen other problems with animations, but mine is with running. When I shift back to third person, my Dragonborn runs just fine and responds to the various key presses correctly. When I switch back to first person mode, they refuse to run more than a second before continuing along at a the normal movement speed.
This works as described no matter how many times I switch between the views. Third person works correctly; first person is broken. I've tried quitting and restarting, but nothing is working. Has anyone else hit this one?
EDIT: I finally figured it out. The game was confused and not showing me sneaking. My target wasn't the sneak mode, and in third person I was clearly standing up. In first person mode, the game suddenly though I was sneaking which is why it refused to let me sprint. I suddenly realized the problem when standing by a companion and realizing I had to look up at them. Two quick taps of the CTRL key and it was fixed.