What I have seen in past is that sometimes "corrupt/not perfect" MP4 videos being played/tried to play would crash the Media Server on the server. Have you noticed what client pcs are doing before or when you see these server errors?
Out of curiosity, I can understand why you might not want to move to Win 11 in an update but are you turning all updates off? I'm wondering if the issue could be certificate/cypher/Edge View/ web related. It might be worth running any updates (other than Win 11 if you don't want it or drivers from MS instead of the hardware manufacturer).
