Locks up machine after playing loded video for a while

Using v5.1.2. Have fast CPU and RTX 12GB 3060 GPU.
Loaded a 1 hour MP4 file 1920x1080 @ 29.97.
Did not turn on any enchantments, just tried playing the loaded video. After 4:53 minutes, the machine locked up and I could hear the hard drive churning. After waiting 8 minutes I rebooted. Hard drive was churning for the entire 8 minutes. While locked up:

  • time on task bar did not update
  • mouse would not move
  • ctl-alt-del had no effect
  • the keyboard and the mouse were not recognized
    I tried 3 times and exactly the same thing happened.
    Only saw it lockup when just playing a video.

Got your support ticket and messaged you back there for the logs.