Ultimatum crash?

I have now both yesterday and today crashed while doing ultimatum, not every time but too ofen.
anybody else seen this?

me too,usualy at last wave.

So i have been playing more now, and id say it like 50% chance to crash

I've been doin survive/circle ultimatums and today I've crashed on 3 consecutive circle ultimatum. I have no (actual) active skills, the only things that trigger are tempest shield and cold snap.
I'm on dx12, I'll try dx11 to see if it crashes too or not although it's awfully laggy on dx11