How reproducible is it? Try to get logs when it happens. On this port, /root has a script that grabs logs on every boot. You could use it (as root) as in

logs will be /root/*smsissue*. Check for some crash messages or something odd. Do not post the logs publicly unless you are sure they don't contain private data, such as IMEI codes/ phone numbers. You can contact me off the list or via PM if needed to send the logs