I have several tracks on my phone that are synced from local files on my computer. But since a few weeks ago, I've been having an issue where some songs display an error message along the lines of "This song isn't available" when I click on a synced local track. This happens randomly it seems. And once this error message has appeared, the track will become greyed out until I unsync and re-sync my local tracks.
I can still listen to the song if I manually click on the track in my playlist, but the song will get skipped over if the song is in queue when I autoplay my playlists, and disables most of the normally available actions for this song (add to queue, for example).
This seems to happen to any synced local song I click, in a completely random manner. I cannot really give reproduction steps for this. Perhaps this happens in situations where the internet connection momentarily drops? I don't really know.
In this screenshot, the first track got the error message when clicked on, and became unavailable and greyed out (despite still being shown as downloaded), while other synced tracks still work fine. I can still listen to the now-unavailable song if I click on it.
The way local files work has been changed recently. There is no syncing between devices anymore, meaning you can no longer sync local files from your PC to your phone. The files have to be uploaded to the phone manually in order to be played by Spotify. More on how local files work can be found in this article.
Hope this clears things up. Cheers!
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