Hi Grisbo. I have exactly the same problem! I've looked around online and you're the first other person I've seen experiencing the same issue.
I've always streamed files from my PC to my TV fine - but sometime around July I first noticed a problem. Any file will now stop playing at around the 2:30 minute mark.
I also wondered if it was a windows update that had caused the issue - but by the time I noticed the problem there were so many recent updates I didn't know how far back to go, how many updates to undo.
I decided to switch from Windows 10 to Windows 11, hoping that this reinstall of a new operating system would solve the problem. But it hasn't!
I'm currently at a complete loss - I don't know what to do - I've tried disabling the firewall - I've even uninstalled/reinstalled my security software. Nothing I try has made any difference.
If you do find any solution to this issue, I'd love to hear it!