I also am experiencing the hitching issue, especially when I first start a video. I believe it only works on Auto Quality, and likely happens when the quality shifts.
I have this same problem, it is infuriating. I'm on Win10, Chrome 54.0.2840.99 m.
I'm having the same problem I had in the beta. Every 10 seconds or so, the video will buffer for a half-second, then skip the video ahead about a second. It makes everything borderline unwatchable.
Are you guys using the 'auto' option? Can you try selecting a specific quality? Does that still give you the same skipping problem?
Yes, even though I select HD, High or Low it doesn't matter. It skips, always, no matter the quality.
I am getting this issue as well, seems to only happen in Chrome as when I try in Firefox its fine