Here i have got the same problem. Accessing playlist, albumlists, artwork from albums etc seems to work. But when I am trying to play the songs i have got the same error notification (translated from Dutch in my case
). The DS audio app on my iphone worked well for a long period but since thins weekend I received these errors and I am not able to use DS Audio anymore. There was no update of DS Audio or DSM in this period and no changes to my Airport were made. I don't have a clue what went wrong.