We have a few adjustments coming in 8.4.2 which should help. 
Thank you for adding the feature to change poster covers! I was wondering if it would be possible to include an option to use the original posters from the movie’s country of origin—for example, American movies could display their U.S. posters, and Japanese movies their Japanese ones. I really appreciate your consideration of this suggestion from users.
With 8.4 I immediately noticed a faster launch of streams from Jellyfin. With 8.4.1 I feel like whatever improvements were made to it were undone.
Although I’m not sure if this update was the cause, or Jellyfin 10.11.7, or something else. Wondering if it’s just me or if anyone else is having this.
iOS 26.5 beta and tvOS 26.4, Infuse 8.4.1, Jellyfin 10.11.7