Voila une soluce qui a marche pour moi, meme si j'ai passe l'étape une
a la fin ca marche sinon vous etes bouré
1. Shuffle (by shaking phone) is turned off.
2. Deleted entire music library on the iPhone itself (under Usage in Settings).
3. Removed all "Manually added" songs. No clue how they were manually added since I've never done that and it was a random list of odd things. But anyway. Remove them.
4. In iTunes, Untick Sync Music. It won't work, so then go through and untick every single thing that's ticked - artists, albums, playlists, etc. Everything. untick it. Sync again. Sync some more. Untick the stuff that gets re-ticked. Sync again. At some point, stuff will remain unticked.
5. Untick Sync Music again. At some point, it will magically work even though you've done nothing different. Have a margarita cos you'll need it at this point. Your iPhone (iPod) will be blank except for all the music that you could download from the cloud.
6. Sync again just to be sure. Have another drink.
7. Add one artist that you KNEW FOR A FACT did not work before. Sync. Drink.
8. Is that artist fixed? Should be. If not, repeat all steps above.
9. Margarita time!
10. It will work eventually. I think it's a syncing issue as well as an iOS 7 issue.