I have Plex Media Server (PMS) on my Synology NAS DS214Play. Streaming everything from PMS to internal player of Plex for my android phone (Samsung S8+) is fine. However I could never stream movies to any external android player.
I tried playing externally on different android video players and here are the error messages:
External Player 1: MX Player:
Error Message: can't play this link
External Player 2: BS Player
Error Message: error opening file file.mkv
External Player 3: Samsung Android Video Player
Error Message: Your device has been disconnected from the network. Connect to a network and try again.
External Player 4: Musics and Video Studio Video Player
Error Message: The location https://192-168-1-16.f0555e353a514959b1 d4cad5e5dffd54.plex.direct:32400/library/parts/59133/1512281606/file.mkv?AutoAdjustQuality=O&hasMDE=1 &location=lan&X-Plex-Client-ldentif1er=324eccdc6697b5bb-com-plexapp-android&X-Plex-Supported-Commands=abort&X-Plex-Token=TOKENHERE cannot be played.
It looks like Plex Android App or PMS submit wrong link to the external player. From the error messages it looks like the file which is being played is named "file.mkv", but the real name of file is something else.
Setting of Plex Android Software:
Player>Device Support>H264 maximum level: 5.1 (Recommended)
Player>Device Support>Audio passthrough: Disabled
Player>Device Support>Optional Audio Support: None
Player>Other players> Use Android media player: Unchecked
Player>Other players> Use external player: Checked
I have installed Plex Android Software from Google Play and it is the latest version: 188.8.131.5283 (c21bd300)
Logs of PMS and Android are attached here.