Yealink STUN phones no audio

[benf]

We have several clients with different remote phones. Most of us are on fanvil but another client has 5 yealinks , since Monday they are often getting no audio on one end of the call, and also the phone doesnt ring frequently. We can call a few times in a row and at least one time it will not ring at all.

This started since this weekends update as far as I can tell and was just wondering if anyone else has seen it? The fanvil phones dont seem to have this issue on another location using STUN but I am going to set one up today to point to the same client to test it as well.

 

[eddv123]

Hi benf,

I cannot see that brand of phone would make any difference in the matter. I use Yealinks myself and they are excellent phones.

With that being said I would not recommend the use of multiple handsets located on a remote site using STUN and would suggest the use of the 3CX SBC instead (if all phones reside on the same remote LAN) you would get added benefits of:

* Audio streams remain local to the remote site and do not have to traverse back to the PBX (PBX delivers audio).

* Added encryption and protection from the tunnel itself.

* Less firewall issues (only one port required 5090 for 3CX tunnel) where STUN uses multiple ports per device.

If you still wish to continue with the STUN setup however I would first review the firmware version you are using, and take a look at this guide and ensure you have everything setup correctly: https://www.electronicfrontier.co.uk/provisioning-remote-phones-using-rps-direct-sipstun/

 

[Saqqara]

Supported way of setting of multiply stun phones at the same site

https://www.3cx.com/community/threa...etgear-nighthawk-x4s-d7800.54620/#post-225296

As above, you may be better off installing 3CX SBC at the remote site

 

[Lee Cramman]

Agree with SBC comments above - it does make life significantly easier, esp when provisioning.

As to the cause, my money would be on firewall / port issues but it might also be worth reprovisioning a single phone and seeing if the problem disappears on that phone...

 

[VoIPTools]

Don't forget that 3CX has expanded the number of RTP ports with 15.5 SP6. 9000-10999 UDP. You may need to adjust your firewall. If you restart 3CX services and the phones start working, it's a good bet this is your issue.

https://www.3cx.com/docs/ports/

 

[benf]

Thank you for your replies, Im sorry I wasnt clear these are remote users working from home permanently. So its several phones at different places coming in . They are all Yealinks (couple of different supported models) , but its one phone per location. It has been working for several months and some close to a year and really have not had issues until after the holiday. Our other 3cx with remote phones are mostly using fanvil but they are all up to date and run behind the same 'config' firewall and pass all the firewall tests.

I just told one of the techs to schedule a restart , check that local win firewall is off etc and lets see what happens.

 

[Lee Cramman]

I just told one of the techs to schedule a restart , check that local win firewall is off etc and lets see what happens.

It's probably worth running the firewall checker as well to see if everything passes.

 

[benf]

Funny you should say that, because apparently there is a whole new range of WebRTC ports I had to open. I forgot the range but it was like 10600-10999 which wasnt showing up when we did the install many months ago .. we opened those up already and are waiting to hear back from the client. Its not every call so it may be a day or so before we hear anything (or hopefully not!)

 

[craigreilly]

the RTP port is pretty random... so that could be it.
it's important to read the release notes cover to cover.
https://www.3cx.com/blog/releases/webrtc-web-phone/

Important: When upgrading to Update 6 note that the Audio-UDP ports have changed from 9000-9500 to 9000-10999. Adjust your firewall configuration accordingly.

 

[Jason Hille]

I had a similar issue where the PBX initiated a call between the caller (Remote STUN) and callee and vise versa, but there was no audio being transmitted or received. Opening up the ports 9000 - 10999 and configuring a SonicWall firewall with the appropriate settings I found from another forum thread resolved the issue.


For what it's worth, the settings on the firewall were to disable the firewall's version of SIP ALG which is linked below:

https://support.siteserver.com/kb/a109/sonicwall-disabling-sip-alg.aspx

Since it's still under observation, I can't say that it has permanently resolved the issue, but so far, audio is working.

Also, it is worth mentioning that STUN is not an ideal remote solution even if it is a feature of 3CX. In my humble opinion; even if it is a solitary remote user, a Session Border Controller (SBC) or site-to-site Virtual Private Network (VPN) is a better solution.

I agree with you, Craig. Change Logs are important to go over.

... it's important to read the release notes cover to cover. - by craigreilly