I had this message pop up at the beginning of my training. And the issue was on for our audio bridge.
The media server is what actually delivers the meeting to you. An issue with it could lead to lost funtionality or a complete disconnect from the meeting. I've not seen that message before, so I don't know what it could have been that the meeting was seeing to cause that issue. Sometimes the classic, close the room and relaunch it can resolve issues like this that may be something as simple as there was a failed or missed connection of your computer to the server.
I also think it had to do something with the new BETA enhanced video/audio option in my seminar room. I turned it on and it threw everything off. But when I started another session without the beta option, everything ran smooth