I saw countless complains online about the cutscene and cinematic performance of Thief's pre-rendered cutscenes.
I have that issue too: it is a problem in-game and not with the hardware or whatever, probably bad video encoding by the developers:
cutscenes are extremely choppy, the framerate seem like it is 5-10 (while it is actually 60FPS - according to live FRAPS test I made). The video lags, lipsync is totally out of sync to the point where the subtitles arrive 5-20 seconds before its time.
Also in cutscenes like the cart in the beginning: it looks like the people don't even move their mouths when they talk.
In short - videos are choppy, laggy, buggy and unbearable. Especially for a game in 2014.
Now I wonder if SE and Eidos Montreal will ever fix this in a patch.
THIEF had an update in steam a short while ago: anyone knows what's new and what got fixed????