Disable Close Captions (CC)

[DigidocTN]

Hello. I have mild dementia, so please forgive my mistakes.
   I am old, retired, and run Jellyfin to watch my collected media from my hospital bed. I share my media using N+ if anyone is interested.
Recently, I started watching the show The Good Doctor. My older TV is not smart, I use a Roku box to make it smart (Roku Express). Using Jellyfin, I access these shows on my server. The problem is, no matter what I do, I get captions watching this show. I plan to try stripping the captions using Wonderfox Converter but there should be another way. Are the captions appearing from the server, or the client? I hate them! I find them very distracting and want them to always be disabled.
   Any ideas? Any suggestions? Want to share files or experiences? I hope to find a solution. I may even make a new friend.

[DigidocTN]

☝Some more information:
The Good Doctor (2017) 01x01 Burnt Food [HD].mkv 1004mb, 1920x1080 (with Sub track). SAME, 931mb, (without sub track)
The file is a little bit smaller (as expected). Now, no subs on the screen (again, as expected). How can I get these permanently disabled on all my files? I have more than 400 series, perhaps 500,000 episodes, spread across 35 hard drives. It is impractical to have to re-encode each file to remove the captions. This may not happen on other Roku models, or on firestick devices. This may also not happen on Android or Kindle devices. 
These files The Good Doctor are samples for others to experiment with. Seasons 01 and 02 contain 18 files, total of 36. You may download 1 (or more) episodes from the following link 🕭: 
https://www.swisstransfer.com/d/1935b5e7...fe8cebfd43

(Season 01 has the captions removed. Season 02 contains English subs). I have more files available for testing/evaluation/conversion if anyone is interested. I want to know the status of the sub track on other platforms. Those who want/need the subs should be able to enable them. Those like me (who detest the subs), should be able to turn them off. Again, I am asking for help. 
My dementia keeps me from understanding this entire process.