What does the debug message "no free events for message" mean when using UNet?

My multiplayer game keeps timing out after like 20 seconds, and I’m getting a debug message that just says

no free events for message
UnityEngine.Networking.NetworkIdentity:UNetStaticUpdate()

Is this why my game is timing out? What does it mean?

Regarding the warning:

See discussion here: http://forum.unity3d.com/threads/no-free-events-for-message-what-does-this-mean.332053/

Quote from the discussion:

here are 3 parameters which will
affect this:

  1. config.fragmentsize

  2. config.MaxSentMessageQueueSize

  3. how fast you are trying to send.

Long message will be divided on the
fragments of config.fragmentsize and
then send. Maximum fragments which you
can send are
config.MaxSentMessageQueueSize (but
this value is shared with other
channels of the connection). If you
will send next Long message just after
that (before network layer be able to
send old ones) this number of
available fragments will low, and you
will possible receive this message.