Didn't realize that was a multiplayer issue as it wasn't stated, but that happens due to lag.
You should always type in /opt fixedframerate 0 occasionally (especially if you have other programs running), and changing your frame rate to 60 would help as well (Esc << Setup << Options << Advanced << Frame Rate (30,60) - 60).
Sometimes, it may occur for no fault of your own (other users pinging, number of clients in the room, particles in the match, et cetera).
Last edited by firebolty; Aug 13, 2012 at 07:28 PM.