Sorry, I don't use FTMC .. but as Marilynlai513 says.. Can be changed in official Kodi.. Easily.
Kindly see my post quoted above and recent posts... Once you've eliminated it's not from your end.. servers..

This is how to get the best from Kodi..

Good Kodi compatible device + enough fast RAM for buffering + Cache size + sufficient stable speeds + healthy home network + no ISP issues + connecting to a capable server (not overloaded)... If any issues arise with one of the above.. you'll experience issues on the playback end. Hence my earlier suggestion, eliminate issues within your control. Once you've done all that and still face issues from a particular service. It's only fair to conclude that said service is the problem..

Hope this explains better.

All servers are not equal all the time. Have options. Switch if one down or too slow. Else tutup the box also can.. Go outside breathe fresh air. 

have u tried other apps that stream the same videos as those kodi addons?

are they better, worse or same?

Found this while browsing around the Kodi forums. Figured it's worth posting here just incase.
Thanks for the share..

i'm using Placenta of Blamo repo, similar to exodus and covenant.

can apply Trakt and RD also...

Mine also cannot work, its weird while others can work. My URLResolver also updated to latest.
Maybe i need to fresh install my ftmc.

Stands for RealDebrid. It's a service that assists with fetching premium links and server priority.. Worth it if you don't mind paying for premium features.

So cheapskate.. Sure, many of us are.. Then better don't complain about no links or slow links.. 
That's the point I was making.. Most complain about no links lah.. too slow lah.. etc.. End up, with a lil money here and there.. One gets significantly better experience. Just like how I've also maintained a Netflix subscription for years.. Do I know how to source for the same stuffs? yep.. but sometimes, you just want an easier route. Plus easier for non-techy folks like my SO.