Every night, the chat gets 20+ users and then just goes crazy.  Lately it has just been repeating someone leaving the room.  But last night it actually worked my worker process so much that it shut down completely.

Once I sent to chat messages, and the second one showed up before the first. 

The only way to fix the chat is to recycle the worker process.

One of the errors is...

ERR (GetUserList): Collection was modified; enumeration operation may not execute.
ERR (GetUserList): Collection was modified; enumeration operation may not execute.
ERR (GetUserList): Collection was modified; enumeration operation may not execute.

We have your open ticket and are working it actively.  We are continuing to monitor your site at night (during your peak time) to try and see the error(s) that you mention, but as of yet, we haven't seen them.  Once the errors occurr, we will be able to trap the what is happening and see why your site seems to have problems with the Chatroom Module.  Please use the open ticket for correspondence and status of your reported problem.  This is the best way to make sure you are getting proper technical support for this issue.

Thank you.

-- Swirlhost Support