When you pickup a piece of clothing from the ground while already wearing clothing it creates a mass pile of duped clothing. If you are civilian then it creates dupes of each civilian clothing type specifically common clothing. This doesn't appear to happen immediately but after a little while after server-run time with reasonable player counts between 35-65 it happens almost every time.
Video demonstration:
www.youtube.com/watch?v=6rXQceebO_Q
My assumption is this has to do with various issues one of which is locality issues but nether the less it seems to happen regardless when you go to take clothing from the ground while already wearing a uniform. This happens the most while being a civilian unit but from time to time have seen it also happen with vests and backpacks (backpacks are very rare).
Server performance:
FPS: 13-20
Player Count: 65
Outgoing Bandwidth: 5500Kbps
Incoming Bandwidth: 1200Kbps
Server Run-time: 3 Hours