Ahh sorry to hear that but glad it's not just me. I was beginning to think it's my character that's bugged. What with the numerous missions that won't complete, this behaviour and a few others that I've reported. Once I was respawned in a wall and could see my feet dangling in through the floor
Back to the Badlands though. Also on that mission I had it happen again for a short period of time. On that occasion it was a dead enemy that was still firing his weapon while lying on the floor.
Had this happen both in missions and in arenas, kind of unfair for the person that shot the beam as it meant I could track them without looking at compass/map. It does almost seem to be tied to maps where there's more than one floor with ramps between