I just purchased a 2012 silverado LT. it has the CAT button, however when you push it it says "XM ONLY FEATURE". when you search the BAND button, it only has AM\FM. there is a seperate AUX button. does anyoen knwo if i have XM? or am i missing some hardware or something? any advice would be appreciated. also if i am missing some hardware, what would it cost to have it installed?