Sometimes one way audio problem

[Aberon IT]

Hi,

I've been looking through the forum to find a possible solution for this problem but so far nothing was able to help me solve the problem.

Occasionally there is a problem that a call is only one way audio. (Usually the first call that is made by the device) It usually happens when an extension makes a call from outside the internal network to one that is also outside of the network. The problem does also occur when one or both are in the internal network.

We are using:

- 3CX 15.5.15502.6
- Watchguard XTM2 series​

When launching the Firewall Check, it reports all tests are good, until it comes to the testing of the Media Server ports. The result is posted below.


I have checked that the needed ports are opened on all firewalls, which is the case and all configurations were done as instructed on the website.

The weird part is that when relaunching the test, the ports that give the "full cone test failed" error change with every launch of this test.

Are these problems related and what could be done to try and solve this problem?

 

[leejor]

Is the 3CX server hosted locally? If so, and you experience audio problems both internal and external, then there may be some other issue involved as well. The failed ports are certainly a concern and will cause outside call issues.

 

[eddv123]

That firewall test needs to be all green before you move on. Despite your thoughts that the firewall is configured correctly - is the type of NAT configured correctly Full feature/One 2 One NAT mappings ?

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

Your firewall brand is covered here also.

 

[Aberon IT]

eddv123, I have followed that exact blogpost and created the SNAT and policy according to the steps shown. Are there any extra settings that need to be configured which are not in the blogpost?
I did find a setting to create a 1 to 1 NAT in a different section of the firewall, yet there is no documentation about it anywhere for 3CX.

 

[eddv123]

Yes it can be a funny one with Firewalls - I use ZyXEL SBG's mostly and you have a setting in the WAN section to "enable Full feature NAT" and a separate section in NAT for 1-1 NAT mappings.

At least in this brand of firewall you need to configure/enable both.

 

[Aberon IT]

I've now both activated a 1to1 NAT and verified all the ports another time, but the random ports still give a "full cone test failed error". It does appear that the amount of errors has reduced though, yet they're still there.
I read in another post that sometimes ports could be reporting an error if they were flooded, so i disabled that option, but with the same result that some ports still fail (also at random)

 

[eddv123]

Not what you want to hear but do you have the means to test another brand of firewall (if you have one to hand ?) I dont suppose you have any sort of local firewall enabled on the server (such as Windows or IP tables)?

https://www.3cx.com/docs/manual/firewall-router-configuration/

 

[Aberon IT]

There is a Windows Firewall on the 3CX server, but I have disabled it while testing, so it doesn't impact the result of the Firewall Check.
Unfortunately we don't have any other firewall to test with.

 

[cobaltit]

Have you tried calling Watchguard support to help with the firewall?