Make sure the Sirius XM antenna cable is not bent or broken.

Please note, messages displayed on your Sirius XM radio screen may vary slightly from what's noted below.
Additional troubleshooting tips specific to your Sirius XM radio can be found in your Sirius XM radio's user manual.
I don't have any issues in any other mode, so I was assuming it was an XM issue...
I noticed this on my red 2011 as well (don't know about my wife's 2011, she hasn't said anything). I haven't tried other stations to see if they have the same problem. Did a Google search "XM artist title update" and found the issue mentioned on in the past, with one poster having the same problem on a Nissan Rogue a couple of days rid of XM (let it expire, stop paying for it), and you won't have any problem... Mine expired, but when they swapped out my radio, I think I got another 3 month trial.
If you are parked in an underground garage, you should receive a signal after leaving the garage.
Make sure the Sirius XM antenna cable is firmly and securely plugged into the cradle.
If I change to a different XM station or FM radio station, it unsticks and works...
but only for the next two songs, then it sticks again. I've seen a couple threads here where people note their center stack randomly reboots. I've noticed since I got my Volt back from the dealer last week, when on XM, the song / artist take a while to update (if they update at all), unless I change channels and change back.
I just noticed an issue where when XM radio is on and a new song starts playing, the radio continues to display the previous song info and does not update to the new one. Thanks, Sirius XM Digital Care Team Trying not to sound too cautious (paranoid), I was surprised to see your post and offer of assistance.