Game consistently crashes during Castrum Mer./Ultima Weapon duties (PC)

[Kandraxx]

I'm still doing the MSQ roulette daily to level friends and I get consistent crashes every 2 to 3 days and WHEN it crashes once then it'll crash again and again until the duty is somehow over.

One time I got a really weird DX11 related crash where I was able to just drag the error popup out of view and continue to play (tho without any sound) and then it froze fully when I tried to give a commend after the boss was defeated.

I have zero crashes in other content or the open world.

Is this a known issue or anybody else having this problem? And just for clarification, no, my game is not 'modified'.

Ed.: forgot to mention, when I alt-tab the game during an unskippable cutscene in one of these duties and click for example the MSN news on the taskbar there's a high chance that the game will also instantly crash/close.