Audio Issues

No Audio

If calls are connecting, this is very likely to be an issue with the end-user's hardware.

• With a SIP phone, check the device connections, in particular network and handset that cables are connected to the appropriate ports on the phone - LAN for network (not PC) and the internal handset port for the curly cable (not the external headset port).
• On a soft-phone client on a laptop/PC, check the volumes and inputs, especially if the end-user has a separate headset.

One Way Audio

This can often point to a localised network issue, possibly NAT or firewall related. The following checks apply:

• That SIP ALG is disabled on any external-facing equipment (normally the main router)
• In the case of software, especially mobile, is the issue apparent both on a WiFi and mobile data connection?
• No network ports are blocked, and the appropriate firewall rules have been applied in the customer's network.
• In shared office environments, we recommend providing the customer with Yealink devices, which support a VPN connection to help with internal networking issues.

"Choppy" or bad quality audio

The following information should be obtained from the end-user:

• How they are connecting, via software or hardware?
• In the case of software, especially mobile, is the issue apparent both on a WiFi and mobile data connection?
• Does this happen only on incoming calls, outbound calls, or both?
• Does only one side of the call experience the problem? If so, which side?

For any audio issues, it will often be useful to obtain a PCAP trace from the connecting device or network. This should provide the raw audio from the call.