Every day or so I'll come across a song in an album that is missing from my phone. Doesn't appear in the Music app, Spotlight search, nothing. But when I plug it into iTunes, it says it's on the phone! I have to delete and re-add the song to get it to appear in the music app. WTF? Anyone else seeing this issue? I'm really regretting my decision to upgrade to iOS10. The honeymoon is over and now it's just constant frustration.