Why Do VoIP Calls Fail After a Firewall Rule Change?

Voice signaling may connect while audio fails if media traffic, NAT handling, or provider allowlists changed.

Checks to make

Compare the change window with call failures, review vendor-required signaling and media destinations, and test inbound, outbound, and two-way audio. Inspect firewall logs and avoid opening broad port ranges without provider guidance.

When to get help

VoIP support can coordinate firewall and provider call-path troubleshooting. Informatix Systems can assess the symptoms, evidence, and next steps. Contact Informatix Systems to discuss this issue.