Calls show connected but cannot hear user

[mcopeland]

Several of our users are having trouble when dialing out. The call will go out and it looks to be connected after the dial tone, but the client on the other end cannot hear us, and we cannot hear them. Once we hang up and redial then normally, we can hear them at that point. This is happening to almost all of our users across a wide variety of different numbers we are calling.

We are all primarily using the softphone.

 

[paulodagraca]

Hello @mcopeland,

Did you run the firewall test on the 3CX server, it all okay and green?

Paulo

 

[mcopeland]

Hello @mcopeland,

Did you run the firewall test on the 3CX server, it all okay and green?

Paulo

We can try and run that. The odd thing is there are a select few users with Handphones and they never have any of the issues previously mentioned.

 

[KyriacosS_3CX]

Please confirm firewall check status, and if SIP provider is supported and using the provided template.

 

[mcopeland]

Please confirm firewall check status, and if SIP provider is supported and using the provided template.

The SIP provider is supported. Odd thing is there are multiple clients all configured almost identical, and they do not report any of the issues we are seeing.

 

[KyriacosS_3CX]

Hi,

Could you check that for the SIP Trunk both sides have each other whitelisted properly, in case Trunk provider is using multiple noted behind a load balancer.

 

[paulodagraca]

Hello mcopeland,

Please try to share the 3CX system setup as being used, so we can try to help you.

Is the 3CX Server installed locally on prem, with VLAN ?, using firewall, what type, or Cloud using SBC or routerphone?
What type of hardphones are in use, what type of "softphone" is in use, and from where? locally on LAN / VLAN / WIFI, other location like home?
What about the Firewall test, green?

Paulo

 

[mcopeland]

Hello mcopeland,

Please try to share the 3CX system setup as being used, so we can try to help you.

Is the 3CX Server installed locally on prem, with VLAN ?, using firewall, what type, or Cloud using SBC or routerphone?
What type of hardphones are in use, what type of "softphone" is in use, and from where? locally on LAN / VLAN / WIFI, other location like home?
What about the Firewall test, green?

Paulo

Is the 3CX Server installed locally on prem, with VLAN? On prem and with VLAN
using firewall, what type, or Cloud using SBC or routerphone? We have a Sophos XG3100 firewall
What type of hardphones are in use? Yealink's primarily one being a T48S
what type of "softphone" is in use, and from where? Both 3CX Windows app and 3CX Web Client is what our users utilize
locally on LAN / VLAN / WIFI, other location like home? occurring both locally and when users are work from home

 

[paulodagraca]

Hello mcopeland,

If i try to analyse this, with the given information:

Calls going to and from the provider seem to be good for some users and not for others.
We could asume that the SIP trunk is fine, as the trunk is working well with most calls, and does not connect to users directly, but always with the 3CX system.

Next we could also look at the the users, that seem to have call problems, they are working from home (WAN) and internally (LAN), still have the same result, so we can state the firewall will not be the issue here, as is does the same on the LAN.

Still we have hardphones working fine on LAN, and not the PC/Laptops/gsm phones working on LAN.
You have mentioned that there is a VLAN for the VoIP, are the IP Phones on the Voice-VLAN, and the PC's on the PC-VLAN, meaning there is difference in contacting the 3CX server?
So this could be a problem with the router??
Try to move a PC/Laptop to the Voice-VLAN, and try to make a call form the Voice-VLAN for testing.

However, let's asume that the VLAN routing is all working fine, and we still have the same issue with the 'Softphones' not working correctly.
This would mean the firewall on the 3CX PBX machine itself is not configured correctly ?
Example:
ports for RTP (default 9000-10499), would be in use by the hardphones
500 ports reserved for audio over WebRTC (default 10500-10999), used by the 'softphones'
Could there be any issue with this setup?

Anyway, hope you can find some information or answer from this.

Paulo