I had the Lumia 900 for about a year now. I have over 1000 songs downloaded via zune pass (not purchased). My PC is windows 7. Thursday I sync all my songs between my Windows 7 pc and my lumia 900. I bought lumia 920 on Friday. Plugged it in, downloaded new windows phone app for my Windows 7 pc. I used that program to sync all of my music to my shiny new lumia 920. All my music that I had now will not play on my 920 because of the DRM message.
All music that I ***PURCHASED*** works just fine because i purchased the DRM rights as opposed to "renting" them w/ my zune pass subscription.
Music that i have downloaded directly to my new lumia 920 from the xbox music store will play perfectly fine. Issue is w/ old content from my pc.