Album art when pinning a music album to Start

[OfficialJab]

When you pin an album to the start screen, what determines what image is on the tile? I had an album that I was pinning, and the art being used on the tile was small with black borders around it for some reason, so on the dark theme it looked tiny and stupid next to other tiles. I erased that music, went onto my computer, ensured the album art was all good in MediaMonkey, and put it back on the phone. It's somehow the same letterboxed art again.

I did it all again, using a different program instead. I put the music back on the phone, and now the image is something I've never seen. Does Xbox Music arbitrarily select its own based on a web search or their own database or something? What's going on here?

 

[BIGPADDY]

I'm guessing they have a database of artist album art, so it would be picking the album art from the database.

The database may contain more then one piece of art work and may change it over a period of time.