I just upgraded my microSD card and moved a whole bunch of my music from my PC and into the music folder after mounting my phone. In some instances, even though I can see all the music files in one album, while accessing them using the media player on the phone, I see a duplicate album with one song in one album and the rest in another.
I have a couple on my device that are the same as your issue. Most of it comes down to how it is organized on your PC. For example, I have all my music on iTunes, under the properties of the song in iTunes you can change the artist name, ablum, and album artist. These all have to match exactly to stay organized under one album.
Are you on OS 7.1? There were few posts here complaining that the music player is having issues on 7.1. I never ran in to any of those, but it looks like even my friends with Bold 9900 have media player issues. Some people complain that the songs skip while playing and others had issues with volume, etc. I don't know if your issue also has to do with that.
I have my music ripped using iTunes and I just grab them from my itunes folder and into the blackberry music folder on the sd card. Was never a problem before on my 9700.
Have you tried looking at the files on iTunes? I'll have to play around with iTunes.
Edit: After looking around on my itunes, I think it has to do with the original file. Go to your iTunes and open the songs that are in the duplicate albums. Right click on the song, then get info, then info, and delete any information under album artist. Then re-sync your music library. If it still shows double album, you may need to delete the music off of the media card and then sync again.
The last time I used DM to sync music onto my Playbook..it took over an hour. So much faster just dragging and dropping. Not sure if I was doing something wrong.
Use the blackberry key to check duplicate files. Check properties, it should show something different for each. I have seen this on my phone when using desktop manager to sync. I drag and drop now. No duplicates this way. It may not be this but its worth a try. Good luck
Properties are identical. Was fine on my old sd card. Strange but I also noticed the album count for the artist is also off. Says 8 albums when there is only 7.