No Audio or Dial Tone?

[Nexent1]

We installed a 3CX for testing and have setup a SIP trunk for this. We are able to place outgoing calls and the called phone rings. However, whenyou answer the phone audio is not available in either direction. We are using the 3CX Softphone on a Laptop for testing and I have confirmed by speaker and microphone are working correctly.

Originally I had dial tone on the Softphone puyt it is also no longer available. This seemed to have happened when I removed the STUN server trying to resolve the non audio problem and this just made it worse. The STUN server re-appeared in the configuration but still no dial tone or audio in either direction.

I appreciate any guidance on setting this up corretly.

Regards,

Robert

 

[leejor]

I would suggest that you remove 3CX phone completely( use Windows Explorer and be sure all 3CX related directories are gone, and Regedit, if you feel confident in using it), from the PC, and re-install. It sounds like (parden the pun), you have caused a problem between the audio drivers and 3CX.

 

[craigreilly]

Windows 7?
Make sure you are not using the HD Audio Driver - but the correct driver for the chipset installed on the laptop/desktop.

 

[albertc]

Try using another sip client for testing purpose and see where the problem is. You can download Xlite by counterpath for free on their website. If the same happens with Xlite, than the problem maybe on your 3cx server or the firewall that stand between your server and your provider. But usually, if you can't even hear dial tone, it is the sip client that is having issue and it does sounded like the 3cx phone is not working with your audio driver.

 

[Nexent1]

Thank you for the replies. I was able to get back so I can hear a dial tone by selecting the audio codec's again. However, still nothing is going over the line. I will download the other SIP client and see if I can test it. I have tried re-installing the 3CX Softphone a few times. I did not remove the registry settings but I will try that as well.

Regards,

Robert

 

[albertc]

One simple test you can do is to dial *777 on your sip phone and see if you can hear echo. If you can pass the echo test, the problem is most likely at your firewall. Give that a try and let us know.

 

[Nexent1]

I completed removed the 3CX SoftPhone and installed the X-Lite. I am able to do the same things as before. I tested the *777 and was able to head the echo clearly. I did not see anything in the Registry I needed to remove for the uninstall of the 3CX phone.

I also noticed that if I press keys on the called phone I can hear the DTMF tones on my softphone.

There is a setting in the PBX for the extension about 'PBX Delivers Audio'. I changed that setting and there was no difference.

I also ran the Firewall Checker on the PBX.

Phase 3 said passed with WARNINGS. Some Functionality will be limited.

Phase 4 said check passed with some warnings. Some Functionality may be impaired.

Are these the cause of the audio issue?

 

[leejor]

I also noticed that if I press keys on the called phone I can hear the DTMF tones on my softphone.

If no other audio is passing through, but you hear the DTMF tones from another VoIP phone, it is probably because they are being sent as SIP messages via port 5060.

At the PC end, I suspect it may be a firewall or security programme causing the issue. It could be the router at the remote end. Making a connection at another hotspot would prove that is, or is not, an issue.

Are the 3CX PBX logs, or the Debug logs in the 3CX phone, any help?

 

[albertc]

Phase 3 said passed with WARNINGS. Some Functionality will be limited.

Phase 4 said check passed with some warnings. Some Functionality may be impaired.

Ok, it is the firewall issue. Your firewall is translating the rtp port to something else which causes the audio stream not passing through the correct udp port. If your firewall support one to one NAT, you can try mapping your wan ip to your pbx lan ip and run the firewall checker again and see if it'll pass all test. Currently, there is no good solution for this kind of problem other than replacing your firewall to a compatible one. Using sip trunk or having remote extension required you to have a firewall/nat device that support static port mappings. For more information, click on the link below.

http://www.3cx.com/blog/voip-howto/static-port-mappings/

 

[Nexent1]

Thank you Albertc,

I am usign a TP-Link Wireless Router. It seems to support Static Port configuation. The following is a screen shot of the port setup.

Am I missing somthing?

Regards,

Robert

 

[albertc]

First, you do not need to forward port 3478 for it to work. Also, can you change the 9000-9049 to udp only? And if you can, run the firewall checker after you made the change and post the result here.

 

[Nexent1]

Attached is the file for the firewall Checker. It looks like it may be doing some port translation? Is this the problem?

Regards,

 

[Aboxtech]

I would look at a better class of router. You can take a linksys 54GL and flash ww-dr or tomato on it. A better option would be to take an old pc and install either pfSense or IPcop on it. The low end home routers will give you nothing but grief....

 

[leejor]

You can take a linksys 54GL and flash ww-dr or tomato on it.

I use DD-WRT myself, mainly for the VPN access, and have never had any problems.

The low end home routers will give you nothing but grief....

Security issues (holes) aside, that is not always the case, in some instances the simpler the router, the fewer the problems.

 

[albertc]

Attached is the file for the firewall Checker. It looks like it may be doing some port translation? Is this the problem?

Yes, indeed. Your router/firewall is doing port translation and therefore causing the problem. There is no way around it and a new one is recommended.

For higher end firewall, the Cisco ASA5500 series works beautifully well.
For lower end firewall, Cisco small business RV series router/Netgear vpn firewall/Edgemarc 4500 series all works well.

I have not try any home base router myself and therefore not sure if any of them will work. But as leejor said,

the simpler the router, the fewer the problems.

Pick up one of those home router from Cisco/linksys or netgear and see if it works.

 

[Nexent1]

Thank you all for your help. I will look at the Lynksys WRT54GC or similar that is mentioned in the information from 3CX. Knowing this now I think the VoIP providers need to provide better information upfront about this. I thing the Firewall checker in the 3CX is a great idea, but it did very little to really help know what the issue was.

Thank you all for your help and I will report back once this is resolved.

Regards,

Robert