I have been following this thread because I have also some random jerky playback on HEVC encodes. Since a few months I would say. I have the impression it was more frequent with 25fps encodes though. It is still possible to watch these, more dropped frames, but rather annoying.
I am on a Vero4K+, and in my case it is HD only, as I don’t have 4K.
What I can add is that if I simply reencode with AVC then the same file is playing 100% smooth.
Anyway I would be glad to be included in the testing if it can help.
I know the question is a bit old, but in mycase of HEVC-HD
yes I have seen and used stop-restart-resume or FastForward and Rewind during playback.
It would often suppress the choppy playback symptoms; but I never was able to reproduce the cure 100%, still random results.
Dropping the link to my issue here as likely to be linked (at least one of them) though don’t see reports of completely black screens for some HEVC playback in the thread:
Cold/warm reboots make no difference to my playback