We have a fairly new installed MX84 installed with a Xelion VOIP setup using Cisco phones. We've already tried via meraki support (who seem to be awful) to try and resolve this issue. If I make any firewall change in particular a firewall rule change all of the cisco phones lose connection and have to be rebooted before they will accept calls. The softphone continues to work though. Have any of you come across this or resolved it already?
This could be so many things. Is Xelion a cloud or on-premise based system?
What do the phones loose connection to? What do the phones report as an error?
I'm guessing the initial drop might be to do with this known issue taken from the 15.23 release notes but is not specific to that version:
Not sure why that would mean you need to reboot the phones but it could be a trigger?
The device is running 14.4 at the moment. The Xelion is a cloud based system. The softphones continue to work without problem its just the physical handsets that stop working (inbound and outbound).