Hi there.
I also had a delayed set in previous alpha 2 and I had the same issue: blank screen/first frame stopped on screen. I had to press pause and play again to resume it.
I solved it by removing that setting. In practice, it works: the new resolution is set in my Sony TV and the video is played. I do not notice any issue or artifact by doing this…
I did not find here anybody else with this problem, so I guess it is Kodi’s. But it would be nice to know it and actually solve it.