Unless you’ve some secret version of Plex with a built in audio translator, there are two possibilities:
- The version in the library really has French audio.
- Plex found another version of the media that contains French audio.
You eliminated the first one. That leaves the second. That’s why I asked you to verify the path and to provide the XML information - to make sure Plex is picking up the correct file.
You should also check the path(s) added to the TV Library. Make sure they do not inadvertently scan an area with working copies, backup copies, etc that might have the undesired audio.
Next step is to remove the file from your system (or to an area not scanned by Plex), and re-scan the library, to see if the episode is really removed. If not, you’ve found the phantom file. If it is removed, then empty trash, clean bundles, and put the show back in the library (AKA The Plex Dance).