Patton ISDN30 Gateway and PBX Delivers Audio

[Wendelspanswick]

V15.5 SP6
Locally hosted server
ISDN30 via Patton gateway on local network
Yealink T23g phones with latest recommended firmware on local network

IT upgraded??? the network over the weekend and we had calls first thing this morning from the client saying they had no speech on any calls. We made some tests and soon realised that as incoming calls to the VM and Conference were working but not calls to extensions it was a RTP problem between the gateway and the phones..
We ticked the PBX Delivers Audio on the SIP Trunks - Gateway - Options for the Patton gateway as a workaround which has got the calls working again but any ideas what IT have done to the network to stop speech being passed directly from the Patton gateway to the phones?

 

[eddv123]

Hi Wendelspanswick,

Which ISDN variant are you using of Pattons ? 4960, 4970 or the newer Trinity models ?

Can you confirm what you mean by "IT upgraded the network" ? Are you talking about 3CX or a network element - if network element please specify - if 3CX or something 3CX related see below:

Firstly I don't think this is a gateway issue as nothing seems to have been changed on the Patton, the only setting(s) that are network related on the device itself is the default route: https://www.3cx.com/voip-gateways/patton-network-configuration/.

But this should only be used if your network includes routed subnets or VPN networks so please ensure (if network changes have been done) that you find out what they are (for example subnet, IP changes).

For clarity's sake can you confirm the issue occurs/occurred on both internal (extension to extension) and external calls to/from the Patton.

If all else fails then trace from the Patton (these devices are very detailed for logging) with the below guide - it covers commands for both Smartware and Trinity OS devices:
https://www.patton.com/support/kb_art.asp?art=446&
Also a guide from 3CX: https://www.3cx.com/docs/patton-isdn-debugging/

You are best looking at the "Media processing section" and perhaps the ISDN side commands (however I think media should be enough).

Note: It is only worth tracing the Patton if the issue effects external calls, it would not be worth doing for the internal calls only.

As a side note - are you are up to date on your firmware for the device always worth a check: https://www.patton.com/support/upgrades/
https://www.3cx.com/blog/voip-howto/patton-smartnode-firmware/