One way audio after resuming a call

[ben_c]

This is occurring on Fanvil X4U and X6U handsets, but haven't tested any others.

The inbound call can be heard by both parties, but when the handset user puts the call on hold then tries to resume, the handset user cannot hear the caller.

I've toggled "Supports Re-invite", "PBX Delivers Audio", and also moved codecs around but the behavior stays consistent.

Any ideas?

 

[JohnS_3CX]

Hi,

Please read the below and give us some more info so we can better understand the conditions:
https://www.3cx.com/community/threads/information-to-provide-when-requesting-help.67558/

 

[ben_c]

Thank you.

• Professional Annual 18.0 (Build 461)
• Hosting with bVOIP
• Fanvil X6U and Fanvil X4U - firmware 2.4.12
• Local provision
• siptrunk.com is the trunk provider
• Firewall checker has passed
• Not sure about custom templates

 

[JohnS_3CX]

Hi Ben,

You say you provision the phones as local, but you have the PBX hosted with bVOIP.

But the provisioning cannot be local if the PBX is hosted outside of your LAN.

If this is the case, you should contact your hosting provider to assist you.

Before you do though, make sure that ALL your extensions have "re-invites" and "replaces" enabled, but at the same time make sure that it is disabled on the trunk. This might fix your issues instantly.

 

[ben_c]

Thanks John. As you can see, I'm green. I do have a support case with them.

I did check the "re-invites" and "replaces" being enabled on the extensions and the trunk having it disabled yesterday. That's what led me here seeking more info.

Thanks for the advice

 

[JohnS_3CX]

One way audio is usually the result of a problematic network/firewall setup and the audio traffic can not flow both ways. So the networking would be the first thing to look at during troubleshooting.

In a normal LAN based 3CX installation, the phones are on the same LAN as the PBX so this is rarely an issue with traffic flow. But if the system is cloud based, the phones need to have some kind of network "path" to reach the PBX. If the networking is setup in such a way that the link is broken, or the contact IPs the PBX sends to the phones are not ones they can reach, we usually see one way audio (ie. the PBX settings instruct the phone to contact the provider's media server directly, but such a connection is blocked or impossible).

 

[JohnS_3CX]

Note: The defaults should look exactly 1:1 like below

 

[ben_c]

Just following up - it was a minor template change. Everything else checked out fine.

Thanks again.

 

[JohnS_3CX]

Hi Ben,

Glad to hear you found it!

 

[Ron Gonzales]

Can you share the template Change?

 

[AliAvali]

Just following up - it was a minor template change. Everything else checked out fine.

Thanks again.

It was a template issue? What was changed?

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