I was testing offline missions and noticed that occasionally when I or a wingman shoot an enemy I hear a local killshooter type ping. I do
NOT appear to be taking damage. It is just a sound glitch. And sometimes doesn't seem to happen.
Here is a film where I believe I captured the effect. Look at the 16-17 sec mark. I don't believe I am being shot directly. I believe a wingman is shooting an enemy.