Noah... interesting in that about a week ago I encountered exactly the same problem with my XM and AFS4500 and AFS 3500 EFIS boxes. I have gone through the refresh process and no changes. I do have the manual for my WXWORX box model REWX91D. I don't get a SIGNAL indication which means no signal detected. So I'm not sure what is happening as I have had 425 hours of trouble free service from this unit. My antenna is mounted under the cowling. I'm wondering if I have a bad antenna. I have a call into AFS tech support. I have ADSB set up and running so I guess I could dump XM. The only reason I have been keeping it is that their radar display is far superior to the ADSB image.

Doug Weiler
RV-7