Give this a try.. it works for me on my Sirius add-on tuner on my honda when it stops working.
I Disconnect the car battery... this not only removes power from the radio and the Sirius but also the lead for the radio that keeps the settings.
Wait 2 mins. then hook up the battery and see if your Sirius settings start working.
Easy to try.. just one connection to pull and put back on.. just make sure you have any anti-theft codes for your radio (if it has it) because it will think it was removed (stolen).
2009 Winnebago Adventure 32h
2006 Terry Quantum 330FKDS (beach getaway)
2003 Aprilia Atlantic 500
2007 Honda Reflex
2 house rabbits "George and MiMi"