@Frozenfire do you have an oculus rift (or perhaps a Vive) connected to the computer that had the issue?
I attached a debugger and broke when UE4 locks up and I see it’s waiting on a thread to finish and found there’s a lot of Oculus calls in the stack. I disconnected my Oculus rift and the issue went away. So it seems there needs to be some check or something.
Hopefully this will give the Epic devs a way to reproduce the issue consistently.