Audio Systems: VW Passat Satellite radio- no sound, usa spec ipod interface, passat wagon

Question
Hi, I bought a used 2007 Passat Wagon that has an satellite radio.   I have an XM account and called them to activate the radio.  There's no sound on the satellite setting, but all of the other radio/CD/iPod functions are ok.  When I crank the volume on the satellite settings, I can hear a hiss, but no audio signal.  The display shows different stations and the songs, but no sound.  Any suggestions?
Thanks!

Answer
In that vehicle if you use the dice electronics or the usa spec ipod interface, in order for the audio to work we find the satellite radio and cut the audio cables and in its place we solder the audio cables from the ipod interface,
to add the ipod you lose the xm

most likely that is the problem and someone cut them for the ipod

pull the radio and remove the ipod interface, you will have to put 3 cables back on the satellite plug
good luck