The skin around his mouth is blurred and smooth through the whole video, even though the top half of his face is clear.
The jaw movement is in uncanny valley territory constantly.
The mouth position doesn't quite track right 100% of the time. It's like those apps that mouth swap, just a lot more subtle.
Much like the weird smiles, occasionally the teeth seem to morph from one frame to the next. This was the final tell for me, but the whole video screams fake.
Teeth changing shape in the jeep video? I think I missed something
Here's a post I made about the with a single gif that is a pretty disturbing morph, facial muscles don't work like that.
https://thedonald.win/p/11PpTxDvpG/americas-first-deep-fake-politic/c/
Watch this video with the sound off (just for sanity): https://www.youtube.com/watch?v=H1JitITYbPM&feature=youtu.be
Just watch the mouth.