There is some keyboard/mouse combination that can cause a character to get stuck switching weapons. The issue comes up during a fight, generally when trying to switch between the two equipped weapons. Once stuck in a "switching weapons" state, the character constantly tries to switch between the two available weapons. The switching is fast enough to prevent the user from being able to fire with either weapon.
I'm not entirely sure what triggers this though. The problem does persist after death/respawn if the character is stuck in this state when they die.
Generally the stuck state lasts 5-15 seconds, though I haven't timed it.