No Audio on calls in or out

[bpcs]

Hey guys,
Has anyone had this issue before, after setting up 3cx with engin all calls are going through but no audio is being passed.
Audio works internally.
I have tried setting different audio codecs with no change.
Hoping its a simple setting I have not configured
We are using yealink T41P phones.
Thanks for your help
Regards
Simon

 

[haywardi]

Without wishing to teach you to suck eggs....

Have you checked your firewall?

Iain

 

[lneblett]

Insure that you have port forwarding set as well as the SIP ALG in the router turned off.

http://www.3cx.com/blog/docs/ports-used/

 

[bpcs]

Hey guys,
I have double checked I have all the ports forwarded and allowed them through the firewall and I have disabled SIP ALG.
running the firewall tester within 3cx says everything is ok, so unsure what this issue could be.

 

[leejor]

If you check the 3CX server log right after an outside call (with no audio), do you see any error messages? Do you have any other outside routes to test with. There are a number of providers that allow toll-free number traffic (may be country specific) for no charge, while a good way to keep these numbers off your regular trunks, it also allows for testing to another provider. for no charge. There are also a few that will assign you a free incoming number, again, country/region specific, but a great tool for testing.

 

[lneblett]

If I understand correctly, engin is a SIP provider in Australia.

For whatever reason it would appear that the RTP stream is not getting to 3CX which is generally a firewall issue. It could be that the router is doing some port translations ......... some TP-Link routers did this. You might also turn off the Windows or any 3rd party firewall that are installed on the 3CX system and try.

If the above is not successful, you should call engin to do a trace on their end. They should be able to tell you if the port you are sending to is the same as the one they put in their Invite SDP. If not, then you may be able to assume the opposite is possibly true as well.

If the ports are incorrect, you can try turning the ALG back on and try, but I have never had any luck with this.

You may have to get a different router, but if you post the make and model there may be others who have experience with it.

 

[bpcs]

Thanks for the info guys,
I have disabled the firewall on the server, and checked the logs but cannot see anything in them.
I am using a Ubiquiti Unifi router has anyone tried one of these before?
Regards Simon

 

[bpcs]

Just did some testing with Engin and everything appears to be working on their side, just tested using X-Lite softphone with no issue.

 

[hashtech]

Please try the option PBX deliver audio under extension settings - other- PBX Deliver audio

 

[bpcs]

No Luck ticking the PBX - Delivers audio setting under the extension.

 

[Frank D]

Does it work using softphones?
Does the phone work (on a different LAN) directly connecting to the SIP provider?
Can you log the traffic to the IP of the phone on the server?
What does the log on the phone tell you? Can you log the traffic on the phone?

 

[lneblett]

Same question as Frank D, but stated in a different way -

When you used X-Lite to connect to engin, were you using it behind the Unifi router? I suspect that even if so, that port forwarding was not done. The problem is that some soft phones have functionality that allow them to be less vulnerable to firewall issues - uPnP, keep alives, auto-Nat, etc. so it may not be an apples to apples comparison.

If possible, do a wireshark capture of a call as this may show you more of what is going on.

 

[bpcs]

Have attempted testing a new router now, set up DMZ for the 3cx server IP.
Attaching images of a wireshark capture as well.

Thanks for all your help everyone.

 

[lneblett]

Not sure that the capture is showing all as you have posted only a portion.

What I do see is that the provider sent back a 183, which is fairly typical. What is missing is the SDP information in the initial invite from 3CX and then the provider's response in the 183 response. The SDP will tell you more about how 3CX and the provider want to handle the RTP streams (which IP and what ports).

From the second post, you are seeing the RTP streams between 3CX and the phone. You should think about using g711a as your primary codec on all devices to include the provider as this is the standard used in Australia as the default.

Without knowing what the SDP indicated, and assuming that the RTP stream capture you showed is complete, the RTP streams are not being seen by 3CX from engin.

Either incorrect IPs or ports are being used or the firewall is not configured correctly or unable to handle. I assume the firewall checker passed with the new router?

You have changed the config to accommodate DMZ and I have a suspicion that the issue still lies in the router/firewall config.

 

[NickD_3CX]

I agree with lneblett, we are missing an important part of the capture.

Try making an Outbound Call and capture it, the open the SDP in the very first INVITE you see for the part of the call between the PBX and the Provider (not between the phone and the PBX), and look for the 2 yellow highlighted values in the screenshot. The one should be the Public Static IP of the Phone System and the other should typically be a port within the 9000-9255 range.