I noticed this the other day too.. Although it looked like I was behind , I actually placed first even though my screen showed two people in front of me. Granite, there were times while in that room that the timer would jump 5 seconds and the start-light would count down in half a second .. So, my guess would be it is the game that is experiencing problems.
On the left side of the game screen, there is an "Quality" button that you can click on, note that you have to be in the game to use it or in uniplayer. Click on it if you haven't already and things should turn to low quality and it helps lowering lag. I think it was just lagging that day.
Yeah I noticed the lag too. I lowered the quality and that did seem to help. Somehow when I would hit the beam at the end in multiplayer and another person was a little bit behind me they would win by a small amount of time.
@Jessbelow: You know, you could've put this in the stickied Exit Path thread instead of bumping this dead one, but read through this Exit Path guide I created. There are some tips in there for reducing lag.
