Trying to start a video player on 6.5 SP1.  Get this error from mm-renderer.  It refuses to create the context.

07.222[2] Unable to handle new client ID '@control.17180311595' (no credentialinfo)
07.223[2] Request from an unknown client ID '@control.17180311595'

Cannot find any reference to this in the docs.  Where are the "credentials" coming from?