Call Quality Issues with 3CX SBC

[TheDestinyGroup]

Hi,

I need some assistance trying to get the bottom of call quality issues I'm having at one of our locations when using the 3CX SBC.

We had been using 3CX SIP Proxy Manager at this location for quite some time without issues until the notebook 3CX SIP Proxy Manager was installed on died.

I decide to replace the notebook with a Raspberry Pi (Generation 2 Model B) running 3CX SBC.

Almost immediately after deployment of 3CX SBC the users at that location started complaining that of issues with the received audio on all calls. They said they had problems hearing what the other party was saying and that the audio of the other party was constantly breaking up. This appeared to happen on both internal and external calls, and happened whether it was an incoming our outgoing call.

I then installed 3CX SBC on one of the PCs at that location and the users at that location and the users still complained of the same issues.

I then decided to installed 3CX SIP Proxy Manager on the same PC at that location and the users said the issue was resolved.

The reason we had been using 3CX SIP Proxy Manager instead of 3CX SBC is that we have been using 3CX SIP Proxy Manager since we first deployed the 3CX Phone System for some 5 years ago and it had been working well so I saw no reason to change until I decided to experiment with using a Raspberry Pi's in place in older PC's and Notebooks as the dedicated 3CX proxy at each location.

Given that 3CX SIP Proxy Manager has been replaced by 3CX SBC I would like to get to the bottom of the issue.

We are currently using 3CX 12.5 SP1, but we were using 3CX 12.5 when the issue first occurred and the extensions concerned are configured for "PBX Delivers Audio", "Supports Re-Invite" and "Support 'Replaces' header". The trunks are also configured for "PBX Delivers Audio".

We are using Cisco 504G handsets at this location.

If anyone has any pointers or suggestions please let me know, and if you need further information please ask.

Thanks in advance.

Les

 

[NikosT_3CX]

Hi,

as a first step please note that the Cisco SPA must be on firmware 7.5.5 . Also port 5090 on the PBX side must be open as TCP and UDP. The templates on the PBX side also to be up to date.
On the PBX side on the Phone Provisioning tab make sure that you have selected SBC as a provisioning method, that you have selected the correct private ip address of the SBC and that you have not changed port 5060 as this is for the communication from the phones up to the SBC and then the SBC changes the port to 5090 as destination to pass SIP and audio through the Tunnel.

For the Pi check the following : http://www.3cx.com/docs/3cx-sbc-raspberry-pi/
and also make sure that it is full up to date with the following :

Update
sudo -s /rights
apt-get update /check for new versions
apt-get install 3cxsbc /install new version

Version
sudo -s /rights
apt-get update /check for new versions
aptitude versions 3cxsbc /version check

i is installed version
p is available version

when only i is displayed installed is equal available version.

 

[MichaelB_3CX]

Hi Les,
Could you please provide the following and send me an email, [email protected]

1.
Full verbose logs of sbc. (Go C:\ProgramData\3CXSBC\3cxsbc.config edit config and set Level=VERBOSE, save and restart 3cxsbc service)
Start wireshark on machine where sbc(windows) is running.
Start wireshark on pbx side.
Replicate test, and collect logs + captures from both side (pbx and sbc).

2.
Install 3CX Sip Proxy Manager.
Start wireshark on machine where proxy is running.
Start wireshark on pbx side.
Replicate test, and callect logs + captures from both sides (pbx and proxy)

Thanks

 

[Vishal_Shah]

Hi All,

We are facing the exact same issue here. We have tried with the Raspberry Pi SBC and the Windows SBC. Did you manage to resolve the issue? If so can you share the solution?

May Thanks!

Vishal Shah

 

[MichaelB_3CX]

First step you need to do is update your system to V15 + SBC Windows V15. We have made refactoring and now the audio quality is superior. SBC for Rasp will come up shortly.

 

[tobiastromm]

Michael, if the remote place has one ATA and one PSTN Gateway.

If the ATA make some call using the local PSTN gateway the audio will stay local?

Thanks.

 

[NickD_3CX]

Is the ATA and the PSTN Gateway registered through the SBC? We have not tested any other devices through the 3CX SBC so I could not say.