I think it maybe the Kiss channel, (21)?. It's been awhile since I've listened to XM but I'm pretty sure that Kiss 21 is a channel from a city. The other 3 are totally a guess.
Okay, I checked out XM411.com
sample post
I hope that when the contracts end for Nashville, KISS, Mix and Sunny that XM gives them all THE BIG F****G AXE!