Hi everyone, TL;DR: My VoIP phones (Polycom and Yealink) stop working, and rebooting doesn’t resolve the issue. Changing the IP address and rebooting does. For context, I manage 46 sites spread across the county. They use Meraki routers and connect to one another via site-to-site VPNs.   Last week, six sites reported that they were unable to make or receive calls. I tried rebooting the phones and other usual fixes, but nothing worked. After lots of back and forth with our VoIP provider, I decided to change the IP address of one device, rebooted it, and it started working again. Odd. I applied the same solution to the rest of the site, and all the phones started working. Strange, but since it was fixed, I considered the case closed. The next day, however, more sites have complained, including a couple of the same ones where the issue previously occurred, saying their phones have stopped working again.   Once again, changing the IP address fixes the issue. The issue is puzzling because nothing has changed with our network infrastructure. The phones at all sites have been working perfectly fine for over eight months, and not all sites are affected.   Our VoIP provider insists there’s no issue on their end and says the problem must be with us. However, the phones at certain sites are deregistering from the VoIP system daily. Despite this, they appear to be working correctly in Meraki, but they lose their registration and seem unable to contact sip.voxivo.com.   At this stage, the same sites are complaining almost daily, and while changing the IP address and rebooting resolves the fault temporarily, it’s only a matter of time before the issue recurs.   Does anyone have any ideas on what might be causing this problem and how to fix it? I’m relatively new to Meraki, so this is outside my current knowledge base. I’ll soon be moving to a new provider that uses 3CX, so I’m hoping the issue won’t persist after the move. ... View more