Mp4 File Subtitles and Roku Tv

[Ewesirname]

This may be a niche issue but I'm having issues with some mp4 files (subtitles) and how they work with my Roku Tv. If you aren't familiar with the Roku subtitle settings, the four options are off, on mute, on replay, and on always (I use on mute). Some files (so far only noticed with mp4 files) will auto change the selected Roku subtitle settings to on always. It seems to be a Roku thing as when I play the same files on another device such as and iPhone or pc. the subtitles stay off. The subtitle settings for each device are the same (preferred sub language: English, subtitle mode: Smart, Burn Subs: Auto). 

Is there a reason for this and/or is there a way to fix it?

[TheDreadPirate]

Are the subtitles tagged as "forced"?

[Ewesirname]

Are the subtitles tagged as "forced"?

How would I check this? Viewing the file in MKVToolNix, there is only audio and video. Opening the same file in VLC Media Player and under the subtitles tab, lists 2 subtitle tracks.

[TheDreadPirate]

In the Jellyfin UI, you can check by looking at the "media info" for the movie/episode.

   

[Ewesirname]

In the Jellyfin UI, you can check by looking at the "media info" for the movie/episode.

No, none of the files are forced.