Why are my calls dropping after 30 seconds?

Sometimes certain calls happen to drop after 30 seconds. This usually always relates to an misconfigured onsite firewall blocking outbound traffic to the PBX.

Here we can see our PBX sends traffic to the device however the SIP ACK (Acknowledgement) message does not reach the PBX within a specific timeout period. Because of this, the PBX disconnects the call.

Below are a couple of solutions to this:

1. SIP ALG is enabled - This needs to be off.
2. Port Forwarding not set correctly.
3. Firewall blocking UDP traffic - All traffic to the PBX should be allowed.
4. You have a misconfigured NAT.