Cannot load M3U8: 404 not found with Plex on RN516

Currently I am trying to get to grips with playing video files with a variety of fomats from Plex on RN516. Some test files are taken from the web, some are home videos taken with a mobile phone and others are ripped from DVDs.

When I try to play some of my video files directly from the Plex web interface in a browser, I get an error message:

Cannot load M3U8: 404 not found.


I find this strange, because the RN516 should be able to transcode up to HD.

Workaround for a similar issue (found on https://forums.plex.tv/index.php/topic/78486-cannot-load-m3u8-404-not-found/):

1) Signing in to MyPlex 2) Ticking the 'Allow Direct Play of AC3 Audio' in the settings

I did something similar, by going to my Plex Settings at http://<mynas>:<port>/web/index.html#!/settings. In Settings -> Plex/Web -> Player, I disabled the setting "Play without transcoding".



Now if I play the same video file, it displays without problems. Even after I re-enable "Play without transcoding".

Next I tried to play video from the BBC iPlayer channel, also with the same Plex web interface.


However, this still gives me the "Cannot load M3U8: 404 not found" error message regardless of the setting.



Most likely because this stream doesn't go through the Plex transcoding mechanism, but is streamed from the BBC iPlayer service to the browser? Has anyone found a solution for that?