I was having problems with my Stiletto 2 not accepting the update from Sirius as well as it locking up while listening to a station. It would lock up so bad that I had to remove the battery and restart. I called Sirius and they have a FREE "Update and Return" service that updates your SL2 at the service center that will hopefully fix the problem.
Here's the link:http://sirius.fthgroupinc.com/sl2.php . Be aware that this site says this Update and Return service is only being offered until July 31, 2011.
I'm sending mine in I'll post an update if it fixes my problem.
Hope this can help others.