Some tracks won't play on Android App

I have tried both the native SubSonic Android App and the UltraSonic app, and I experience the same issue.
I'll add an album to the playlist before my morning commute while I am home, so that most of the download happens on Wifi. I then start my commute and the first 5 or 6 tracks will play flawlessly, but then the next track will not play at all. I try the other ones as well, and nothing. I can go back to the previous ones, and they still play fine.
One thing I do notice when I check the log in SubSonic is that I will get this:
[1/22/15 9:07:11 AM EST] DEBUG InputStreamReaderThread (/var/subsonic/data/transcode/ffmpeg) Unrecognized option 'b:a'
The odd thing is that, they look like they have already downloaded too. If I try to add new tracks to the playlist now (using mobile data), I get a downloading 0B, and that's it. No download, no play.
Any ideas what could be happening?
Currently cannot play any new tracks on the playlist.
I'll add an album to the playlist before my morning commute while I am home, so that most of the download happens on Wifi. I then start my commute and the first 5 or 6 tracks will play flawlessly, but then the next track will not play at all. I try the other ones as well, and nothing. I can go back to the previous ones, and they still play fine.
One thing I do notice when I check the log in SubSonic is that I will get this:
[1/22/15 9:07:11 AM EST] DEBUG InputStreamReaderThread (/var/subsonic/data/transcode/ffmpeg) Unrecognized option 'b:a'
The odd thing is that, they look like they have already downloaded too. If I try to add new tracks to the playlist now (using mobile data), I get a downloading 0B, and that's it. No download, no play.
Any ideas what could be happening?
Currently cannot play any new tracks on the playlist.