If those videos are HDR videos, then it's possible that (major) hiccups occur. The RPi4 is not 100% compliant just yet for those types of video.
Hello I have same problem, with 4k crash, I install 9.2.0 version and same problem, if I forward system freeze. Will work the 4k or UHD files? Or may be better buy a Raspberry 3 ?
Thanks.