diff --git a/app/services/episode_disk_title_selector_service.rb b/app/services/episode_disk_title_selector_service.rb
index 0e24425b..c6d1479f 100644
--- a/app/services/episode_disk_title_selector_service.rb
+++ b/app/services/episode_disk_title_selector_service.rb
@@ -34,7 +34,7 @@ def episode_disk_title(episode)
   end
 
   def disk_titles
-    disk_titles.sort_by { _1.segment_map.sum }
+    disk.disk_titles.sort_by { _1.segment_map.sum }
   end
 
   def select_episode(disk_title)