itunes channel does not cast to chromecast audio or chromecast tv
I have installed plex media server on a windows 10 laptop. I use the Chrome browser to access Plex Media Server web app. I have been able to "cast" plex media server music library to my chromecast audio and TV. When I attempt to do the function via the itunes channel, it will not cast to either device. Music will play locally within the itunes channel but as soon as I click on the cast button the musics does not play until I disconnect. I would prefer not to rebuild or import by itunes playlists.
I have searched the forums and have not found a resolution.