I have corrupted metadata in lots of tracks, even ones I added directly from Music... after changing the text in song titles.
Found this suggested fix from : If your music library shows incorrect details with iTunes Match or Apple Music, and you previously cancelled an iTunes M… but wouldn't this delete all the tracks I directly added in Music? My understanding is even the downloaded Music tracks disappear when you delete those tracks from your iCloud Music Library?
Posted on Dec 29, 2015 2:28 PM