[pstrg]

Kodi 17.4 / Windows 10

Movies that have external (srt) subtitles have them properly named according to language, as movietitle.en.srt; movietitle.pt.srt etc.

On the main installation (interface language: English) Portuguese_Brazilian is selected as preferred subtitle language.
If a movie that has both English and Portuguese subtitles is played, the later is automatically chosen, as expected.
Also, it's possible to toggle to the other language.

On the client installation, which accesses the main one through UPnP, interface language is also English and Portuguese_Brazilian is also set as preferred subtitle language.

However, if a video that has both English and Portuguese subtitles is played on the client, the English one is presented, in disregard to the setting.
And if one tries to toggle (the windows shows the current one is correctly identified as eng) it's not possible to change.
If a movie has only one external subtitle, it is presented, even if it's not identified as English.

Tried to change interface language on each side, and both sides, to Portuguese_Brazilian but no way - movietitle.en.srt is the subtitle that plays and it's not possible to toggle.

Is it a bug or is there something that can be done?

[Klojum]

It's probably one of those 'features' of UPnP. I had something similar some time ago when playing videos directly on my TV via UPnP/DLNA. So either you remux your videos with all the subtitles you need, or you find a different way of sharing your videos across your network.

[pstrg]

It's probably one of those 'features' of UPnP. I had something similar some time ago when playing videos directly on my TV via UPnP/DLNA. So either you remux your videos with all the subtitles you need, or you find a different way of sharing your videos across your network.

Alas, I'm afraid that remuxing would not be a practical solution - way too many movies.

[pstrg]

Update

Discovered, by trial an error, that it's not because it's English that an external subtitle is automatically chosen.
It's simply because movietitle.en.srt happens to be the first in lexicographic order among other subtitle files in the folder I used for test.

In fact, if I copy an English subtitle and rename it as movietitle.cs.srt the system (Kodi + UPnP/DLNA) chooses it, because it comes before movietitle.en.srt.
In this particular case, Kodi thinks the subtitle is in Czech, since cs is the ISO 639-1 code for that language.

An interim (and partial) solution to the problem would be to name the preferred language subtitle as simply movietitle.srt, so that it comes before any other.

Crude, but works, even though it still won't be possible to toggle to another language.