VLC just released a major update. I don’t have any 4K video to test it with, but I think it was supposed to help with that. Could anyone confirm that?
Provided that your CPU and GPU are good enough. I am on a 7600k and 1060 3 gig and VLC still struggles with 4k for me. Leawo Blu Ray player will play 4k files smooth, at least on my hardware.