I just finished playing a deathmatch and i opened a new fight room in a new window then closed the window with the deathmatch screen.
While i was playing the first game i got this error: http://img690.imageshack.us/img690/2244/picture3dz.png
and then i found myself in Fight Club.
Some say it is because you have been inactive for too long in the room.
I say they should make the "kick-out" time longer.
The problem is i was playing a game in an event room. I had nothing to do with deathmatch anymore.
I lost connection to a DM, refreshed the page when I had connection back and was sent to the Fight Club.
I had the opposite happen last night, I was playing in Fight Club, and half way through noticed that I seemed to be getting DM points, and even managed to complete a DM mission by winning it.
Clear your cache and restart your browser. If that don't help you can try a newer version of flash and/or java.