I have a mobile phone car kit installed and the installers couldn't get the empeg to mute when the phone rings (ATT?)

Is it possible to do this with the empeg? Does it have something to do with the "Mute" setting under Player Configuration??

Also, I had all my music in soup views but no playlists, and created A, B, C, etc playlists and dragged from the Artists soup view to the relevent alphabetical playlist, but it didn't create Artist and Album nested playlists as I thought it would. Is there a way to make this happen?