When you have many libraries where some are in local languages and some in foreign you really need to be able to set the audio and subtitle settings at the library level. For example on English TV series library i don't need subtitles but on my Asian Tv series library i need to force subtitles. If you don't dot his then the subtitles will not work when you sync and you need to set them for every episode you want to play so you can't just use the button to play the next unwatched episode in a series.
The work around i currently have to use is to run 2 plex servers in 2 virtual machines pointing to the hosts file library but this is far from ideal and a bit of a pain switching between the servers on the new plex client. I only run 2 servers purely to set the subtitles and it is a huge waste of resources.
Even if the settings on the library just override the user level settings if they are set would fix the issue for all uses that need subtitles for some of their content.
In simple terms duplicate or move the Language tab from the server preferences to the settings on each library. There is already a setting there for the language of the meta data but there needs to be audio and subtitle settings there as well.
