Alright, so I was playing Extraction with two friends of mine (all on PS4, I'm playing via buddy pass if that matters for some reason). Anyways, I'm playing Pulse and we've cleared the enemies in the airlock that transitions between zones and all of us have voted for it to continue. As the yellow gas filled the room my character just randomly fell over and the stasis foam activated message popped up, and I started spectating.
Neither myself nor my friends heard the sound of any enemies attack (which makes sense since we didn't see any) so none of us have any idea what the cause of it. My Pulse had been at 96 health, and even though I hadn't been downed before this did cause the foam specifically, rather than just knocking me.
That's all the information I have, hopefully it can be fixed. This is the first time anyone I know has seen anything like this despite playing fairly regularly.