Anyone else having trouble with SIP (both pjsip and chan_sip) after the latest update to asterisk (asterisk13-core-13.26.0) that was released last week?
We started experiencing extremely weird behavior in SIP on all our systems that were updated and are running that version.
We are unable to reliably replicate the issue to figure out what the root cause is but it manifests itself in a complete breakdown of SIP. No incoming or outgoing calls can be processed, no extension to extension calls seem to work properly nor am I even able to do a simple “core restart now” to restart asterisk. The only thing that seems to fix our problem is a complete reboot of the system until it breaks again.
We had a system that failed every 10 to 15 minutes and then we had one that failed every few hours. Call volume seems to matter as systems that receive fewer calls seem to last longer.
I just now discovered that the systems that we were troubleshooting had all been running the same, latest version of asterisk that were installed Friday morning.
I just now rolled back those updates to see if that will make a difference in functionality.
I have just updated our FreePBX to 13.26.0-1.sng7 and am seeing repeated hangs with SIP connections blocking softphone connections - the softphone registers and then though asterisk appears to still think it is connected though the softphone can no longer connect - only way out of it is restart asterisk (fwconsole restart - or whole machine) - sometimes i have had to “killall -9 asterisk” - just getting to grips with this now and seeing if anyone else has seen this issue.
This also happened to me, but not to the degree of crashing every 15 minutes. I was running FPBX 14, under Asterisk 13.26 and after a few seizures  over the course of a couple days, we decided to move to Asterisk 15.7.2 which stabilized us for a few days. But then the seizures started again. I saw this post here, and attempted to move to Asterisk 16, but yum had errors “Package does not match intended download”
I am currently back on Asterisk 13.21 hopefully stabilize. Thank you for the instructions on how to yum downgrade.
 I say “seizure” because the box did not lockup - the CentOS linux was completely functional, and “amportal restart” would restore our environment until the next error condition.