Wasn’t there a module update for SIP a few days ago ? I have noticed that systems that only use ChanSIP have suddenly started showing the following error in the Full log from about 13 Jan20:
ERROR[C-00000000] pbx_functions.c: Function PJSIP_HEADER not registered
They come in blocks of 12 and could be inbound calls. I have been through all the settings and nothing has changed for a couple of years.
Given that PJSIP is not available on these boxes I am a little curious on how to rollback to an older module to check.