iTunes Match sometimes gets stuck in an unsynced state.

[lgarron]

The following have been happening for years:

• A song takes long to upload — hours or days for a file that can be uploaded in seconds. Even if Music.app is open continuously, and even if the app is restarted few times.
• A song shows up in the cloud as gray. Tapping it on mobile says "This song is not synced across your devices. On your Mac or PC, got to Apple Music or iTunes for Windows and in Preference, select Sync Library". But "Sync Library' is enabled on the source computer.
  • There's also an "Add to Device" context item in the desktop app that... does nothing.

I don't recall a song that was never eventually synced, but I live in perpetual worry about it.

The only workaround I know is to add another copy of the song to the library, carefully reproducing its metadata and e.g. which playlists it's in.

[lgarron]

I know sync is not always easy, but I've literally been paying Apple for iTunes Match longer than I've continuously paid them for anything else. They haven't even thrown in some sort of debugging mechanism to see where the inconsistent sync state might be.

It's been over a decade, and it's still failing at its core job. :-/