Original issue with cast images is unresolved and having a hard time to understand, how missing cast / actor images relate to local router settings as other TMDB metadata is showing and information is retrieved just fine.
Trouble with both old and Plex beta agent: Missing Actor Thumbnails
More hit and miss behavior: Many actor images missing
Many users reporting issues: Metadata not working / incomplete
More: Pictures of actors disapear
@trumpy81 as it obviously worked as expected for you, can you share your settings for agents and I’ll try to replicate that?
