iPhoneX and MacBookpro use infuse to play 4k video without freezing at all.If you switch to apple tv 4k and play with infuse, it will not play, or there is color difference, or there is sound and no image. What is the reason?
Are you attempting to display to a 4k capable tv via a connected TV? I
What type of videos are these? HDR, DV, etc…
Can you provide a bit more info about what happens when trying to play these? Are you receiving an error message?