When inside the andas vault near the end of the quest if you summon something at the trigger for tholer andas' dialog it will infinite loop the dialog and you must force quit the game

1. activate the dialog trigger

2. step outside the dialog activation area

3. summon something inside this area or have it run to inside the area

I was specifically using the amulet of shades to summon a bonewalker. This bug is sometimes difficult to reproduce but it is game breaking. It seems you have to be outside the trigger when the summoned thing goes into the trigger.