Mesh sliding

I have a hat for a character that I have attached to the head bone of my rig. As I step through the animation in the sequencer, things are great, the hat locks onto where the head is at. When I try to make a video or image sequence however, the hat slides around a tiny bit. When I step though, everything is fine. Any suggestions?

P.S. I’ve set the hat to movable and stationary with the same results.

Why not try to attach to a socket? Make one on the head, attach the hat on it.
this usually works 100% fine in anything. I have several (over 30) items attached to sockets on the same character. I’d have noticed if one of them slid out of place.

Additionally, the issue you are having might also e releated to sync - if say your hat mesh has bones too.