Read the following article, see the clip there and please read also the readers comments: Club 3D DisplayPort to HDMI 2.0 Adapter Connects Skylake NUC To a UHD TV – Mini Review – The NUC Blog
Probably the link will be blocked by Intel, so copy it and paste in your browser.
Hope this will help
Thanks for the reply. I took a look at the thread and comments and nothing there helped or seemed related. I don't think this is an adapter problem. The NUC basically hangs for a second every 5-10 seconds while playing 4k video. I can tell this is the case because the mouse and computer also locks up and you can't interact with Windows while this happens. It seems more like a resource issue and that 4k video is too much for the NUC to play.
From the NUCBLOG thread I've understood that NUC is capable to playing 4K video. Could be that you have some other problem and may be in Windows. I'll will suggest you to prepare Live USB with LIBREelec and try KODI on other OS installation. If it will play without locking your NUC, something wrong is in your Windows. Preparing such SSD is very easy.