3CX calls dropping 29:30

[SpaceCowboy]

Hi,

I have been troubleshooting an issue of come calls dropping at 29:30.

The SIP provider has narrowed it down to re-invite happening around this time, coming from 3CX.

I've checked over the Codecs where it looked to be all correct.

I also noticed "Supports Re-Invite" is enabled, maybe this is causing the issue?

Attached the pcap and explanation from the SIP provider.

Any help would be grateful!

 

[JohnS_3CX]

Hi,

Why do you have re-invites enabled on your trunk?

Is this a 3CX Supported provider?

 

[VoIPTools]

It has been a long time since I have seen this problem, but some firewalls force a renegotiation of ports on a scheduled basis. Given that this happens at the same time (every 30 minutes), this seems like a scheduled renegotiation either by your firewall or your SIP provider.