Solved Auto Provisioned IP Phone has no audio between extensions

[fendytan]

I have installed a 3CX v15.5 on a cloud VPS (OVH). I ran the firewall test and the checkmark is green.
I added several extensions from the dashboard and using 3CX clients on Android and iOS, calling between these extensions are good.

I want to add a Yealink T19 E2 from my home (internet fiber connection with dynamic public IP). Using "direct SIP - STUN remote", the phone was auto provisioned and then added successfully to extension 121. But calling from 121 to other extensions and vice versa has no audio voice. The phones can ring, but no audio. I have checked the "PBX delivers audio".

Do I need to do port forwarding on my home router? I always assume that the port forwarding is always needed for the server (IP PBX) but not for the IP phones at the remote location.

 

[fendytan]

Yealink T19 E2 is supported and also updated to compatible firmware.

 

[Robertos]

hi Fendy,

yes you will need to do some inbound port forwarding on your internet gateway to this inside Yealink phone when using STUN for remote site phone.:
Assumed you have only 1 remote phone at this site you are testing with
Assumed that in “Options” tab of the extension, you have removed “Disallow use of extension outside the LAN” to allow phone to register, you will need to:

UDP destination Port 5065 from 3cx to your Internet IP -> Forward this to your Yeallink phone's IP address (used for Signaling)
UDP destination Ports 14000 to 14019 from 3cx to your Internet IP -> Forward this range to your Yealink phone's IP address (used for audio stream RTP)

These are the default values and should match SIP and RTP values defined on your 3CX server Extensions-> Phone Provisioning-> IP Phone.

 

[fendytan]

Thank you @Robertos.

 

[Robertos]

Pleasure

 

[YiannisH_3CX]

Please check our academy section regarding remote extensions as it contains all the necessary information https://www.3cx.com/3cxacademy/videos/intermediate/configuring-remote-extensions/

 

[fendytan]

Noted. I was under assumption, I could just bring my auto provisioned IP phone (not softphone) to anywhere (hotel, public places etc) and then connect it to the available network, and voila. I was wrong.

It is working now after setting the port forwarding.

 

[YiannisH_3CX]

Noted. I was under assumption, I could just bring my auto provisioned IP phone (not softphone) to anywhere (hotel, public places etc) and then connect it to the available network, and voila. I was wrong.

Some firewalls allow this especially if there are not multiple phones behind the same IP but if you are facing audio issues you need to perform the port forwarding.

It is working now after setting the port forwarding.

Glad to see the issue has been resolved.