This has happened twice on my 1520 now, which I've had since it came out, and I've had the storage card for about a week I think. The first time was yesterday and the second time just now.
The problem is that all my playlists disappear, and then when I go into XBox musiconly artist or album that shows up is "unknown artist" (for which I have a few songs) but when I swipe over to songs all the songs are still there. I fixed it last time by deleting all the music off my phone and starting over again, but that was just an hour ago maybe.
I did have connect with xbox music on, so I've switched that off and will see if that helps. cloud collection and now playing were already turned off.
The problem is that all my playlists disappear, and then when I go into XBox musiconly artist or album that shows up is "unknown artist" (for which I have a few songs) but when I swipe over to songs all the songs are still there. I fixed it last time by deleting all the music off my phone and starting over again, but that was just an hour ago maybe.
I did have connect with xbox music on, so I've switched that off and will see if that helps. cloud collection and now playing were already turned off.