I was watching my brother play on an experimental server, US NY, and he jumped off of the bridge on the road to chernogorsk (steel bridge with trains underneath) and He must've landed on uneven terrain or something, because He went unconscious and it did the leg breaking sound, but it kept repeating the sound, over and over again, and didn't stop until he chose to restart and spawn again. This may be a glitch with going unconscious on slopes or when landing on the railroad tracks.