Not all of my movies are available through my network conection

Hello,

 

I have both my apple TVs set up through a Media NAS Box with 1300+ movies and TV Shows. They are in separate folders with Movies in one and TV shows in another. For the last few months when I add new movies to the NAS box they do not show up in the Movies folder when viewing through the Apple TV Fire Core Media player? I have reset the apple TV and have the latest update, but they still don’t show up? My only thought is that it might be blocking the titles like after 1000 titles or something? There are 1100+ movie titles in the one folder, should I split them up or is that not the issue? The strange thing is that it does not do it to every movie I add, it totally random?

 

Any Ideas?