Recently I've noticed that when I go through Album Artist to an album, some tracks are listed twice. These files are not duplicated in the database. The tracks only appear once if I go through the Album view from the main menu instead of going through Album Artist, and also only show once under All Tracks. It is also not possible to select both listings for a duplicated track simultaneously; selecting one will deselect the other. Playing the album by pressing on a track does cause the affected tracks to be added to Now Playing twice though.
Here is a screenshot showing one affected album after going through Album Artist. I had pressed Select All to show that only one listing for each can be selected.
And here is a screenshot showing the same album after going through Album on the main menu.
I'm using build 361 with a Nexus 5 and a Nexus 7. The issue occurs on exactly the same tracks on both devices. I have tried deleting all of the media from one device and resyncing but the same issue occurs with exactly the same tracks again.