1 Way and Both Way Audio Issues

[john.barnhill]

I have an office that is sitting behind a UniFi Dream Machine (firewall). We are getting intermittent either 1-way or 2-way audio issues, but then sometimes it works fine. I tried a YeaLink T54W setup as a router phone and that did not work. I then removed the router phone configuration and installed the SBC on a PC on the same network. Same issue. I have tried setting "PBX Delivers Audio" too. I am at a loss for what else to try? The phones are on the same network. This happens randomly when calling the between the phones onsite, cell phones and other phones on the same PBX at other offices.

 

[KyriacosS_3CX]

Hi,

Phones on-site having call quality issues (with PBX Delivers audio and Recording off) would indicate some problem with your LAN configuration. I would start by investigating the local switches.

You can also use the call quality monitoring and packet capture to gain some further insight, but first check that your LAN is not underperforming.

Best,
KS.

 

[john.barnhill]

The phones are currently plugged directly into the switch at the network rack for testing. There are only 2 VLANs (Staff and Guest) and both phones are on the Staff VLAN. I do have call recording enabled, is that a problem?

 

[KyriacosS_3CX]

Call recording would mean all calls, including local ones, are going to the 3CX server and back. Disabling and checking call quality when calling between the phones on the local switch will help isolate whether the problem is in the internal network, or outside.

Calling from an outside line in, with call quality monitoring active, should show if there is an issue related to the SIP provider or the 3CX to phone leg.

Also of course check if the local internet link is oversaturated.

Calling 3CX mobile app to 3CX mobile app, in a good connectivity environment, might show if the server itself is for any reason causing some trouble.

You do not mention if there is an issue when phones in other offices call each other, or call outside numbers. If these calls are fine, then whatever the cause is, it's within the LAN+Internet link of this one location.

 

[john.barnhill]

Plan on troubleshooting this more tomorrow, will update

 

[john.barnhill]

Call recording would mean all calls, including local ones, are going to the 3CX server and back. Disabling and checking call quality when calling between the phones on the local switch will help isolate whether the problem is in the internal network, or outside.

Calling from an outside line in, with call quality monitoring active, should show if there is an issue related to the SIP provider or the 3CX to phone leg.

Also of course check if the local internet link is oversaturated.

Calling 3CX mobile app to 3CX mobile app, in a good connectivity environment, might show if the server itself is for any reason causing some trouble.

You do not mention if there is an issue when phones in other offices call each other, or call outside numbers. If these calls are fine, then whatever the cause is, it's within the LAN+Internet link of this one location.

1. I experience 1 way or no way audio regardless of having call recording on or off calling between desk phone extensions or cell phones, but the3VX mobile app works perfectly fine.

2. These phones are experiencing the same issues at several of our homes in our home lab environments. There isn’t an internet saturation issue at these locations.

3. The 3CX mobile app works flawlessly

4. We get audio issues both on outside lines or between extensions. The PCAPs show the audio stream is there and making it to the phones but you can’t hear the other person.

Kinda getting desperate here

 

[KyriacosS_3CX]

What phones are we talking about, by the way?

 

[john.barnhill]

What phones are we talking about, by the way?

We are still in the testing phase of 3CX, so I started with two Yealink T54W one as a router phone, at one guys house. We experienced audio issues between both of these phones. I have also experienced the issues using a variety of Poly VVX450 and Yealink T46U testing from other locations. Interestingly, I have some legacy phones on at my office that seem to be working fine, VVX 300-311, 400-411, Yealink T46S, Yealink DECT W60B

 

[KyriacosS_3CX]

Are the problem phones using the latest 3CX firmware and templates?

 

[john.barnhill]

Are the problem phones using the latest 3CX firmware and templates?

Yes, I think so, if there was an update for the phone, I ran it via the admin center. The Yealink I know for sure was because it wouldn’t work until I got it on the correct firmware, then 3CX was able to update it again to the latest version

 

[KyriacosS_3CX]

We have to assume a networking issue somewhere. But whether it's the actual firewall or something else in the network is not easy to trace.

Let's do an audio quality test through the admin panel, and see if it points to anything.

Also if you can, do a wireshark/pcap capture inside the network during a problem phone call, maybe it will show who can't talk to who. This might need configuration of a switch port to capture all traffic going through that switch to show anything meaningful.

 

[john.barnhill]

We have to assume a networking issue somewhere. But whether it's the actual firewall or something else in the network is not easy to trace.

Let's do an audio quality test through the admin panel, and see if it points to anything.

Also if you can, do a wireshark/pcap capture inside the network during a problem phone call, maybe it will show who can't talk to who. This might need configuration of a switch port to capture all traffic going through that switch to show anything meaningful.

I see how to enable the quality test, but how do I review the results? THANK YOU FOR THE HELP!!!

 

[KyriacosS_3CX]

In the Call Log report, the 3 dots at the end of a monitored call will let you view it.

 

[john.barnhill]

In the Call Log report, the 3 dots at the end of a monitored call will let you view it.

How can I send you this information privately?

 

[KyriacosS_3CX]

Did this call present any issues when listening normally to it?

 

[john.barnhill]

Yes this was a 1 way audio call. My engineer and I plan on collecting more data today so I’ll circle back with more logging

 

[KyriacosS_3CX]

Still can't shake the thought that something in or at the edge of the network is messes up, and it's not something I can have any real visibility on.

Just as general test dialling *777 is the loopback extension, it plays back to you anything you say. This can allow testing devices in isolation.

Would it be possible to strip things down, have a switch that has just the SBC, uplink and two phones, to see if without anything else it works OK?

 

[john.barnhill]

The loop back works fine with the Poly VVX 450 but nothing on the Yealink T46S on the same network with a local SBC installed on my laptop for testing.