I’m quite unsure if this is being looked into by Plex team. I’m trying to mention here a couple of Plex people who are posting into the release announcement for the Android player and Chromecast: Plex for Android and Plex for Chromecast - maybe they will pick this issue up. It’s affecting a lot of users and there are at least 4 distinct threads and quite annoying that a Plexpass feature is not working for months…
@ManuelPG @romancamelia @marekszulik @duncanbeevers could you please check on this?
Summary: using Plex app, casting to (for eg Chromecast) works when the content is played from the Plex server. Problem happens when you sync media to your phone/tablet and try to play back the phone/tablet synced content if (for eg) your Plex server not available