What sort of system do you have your server installed on? maybe it Plex does not have permissions to see/read the files. Are they on a local drive or a network drive? Did you manually tell it to scan or are you expecting it to detect new files and scan automatically? What are some of the track file names ( If iTunes made them, I’m sure they are ok, but good to confirm)
01 Goodbye, World, Goodbye
02 Great Is Thy Faithfulness - How Big Is God - How Great Thou Art Medley
03 Just A Little While - The Meeting In The Air Medley
I have plex installed on a synology nas. Been running it with movies and tv shows for years. I was reading your comment a second time, and as I’m typing it hit me… permissions, plex doesn’t have sufficient permission!