Has anyone else had trouble casting Time Stop in Cyrodiil? I decided to slot it and try to use it to help get rid of an enemy ball group running around inside a keep, and it repeatedly self-aborted. My character's arms would start the wind up but would just quit after half a second or so, and my magicka bar would drop as if it had cast, but there would be no effect. This would happen over half the time I would try to cast it.

There was a lot of fighting going on but none of my other skills had any trouble firing, and it didn't seem particularly laggy.