well yes youtube is fine on other devices but my xbox one x and my desktop pc are really the only devices I have that can do 4k video. However the problem doens't happen on any resolution on my one x if the codec is vp9(303) and below, when it shows up as vp9(315) which I think is 4k 60fps and the number below 315 is 4k 30fps is when the glitches appear and I can have up over 1k of dropped frames from this glitch.

So I guess the problem only shows its ugly head when there is a 4k 60 video but 4k 30, 1080p 60, 30 and anything less works just fine. It used to never do this for the time I've had this xbox one x which is a project scorpio launch.