I seen some posts where some subscribers claimed to be receiving the Sirius channels for free even if they only had the AT60 package by going to the EPG. They may have scrambled them as a result or Sirius may not have wanted their channels in the clear since they think it may affect their pay service that they have for the car or home. I would say that would explain why the Sirius channels got scrambled and the other audio stations didnt. I also read a post where someone mentioned that they would never bother with it, but they did.