Symptom

Yealink phones using Yealink WiFi adapters (e.g., Yealink WF40), experience garbled and choppy audio. Additionally, if the phone using an adapter reboots, or a new config is generated, it will likely downgrade the adapter firmware.

Applies To

All Yealink phones using the USB WiFi Adapter

Resolution

In the case of the firmware being downgraded by a phone reboot or config change, complete the steps to reconfigure the adapter.

  1. Factory reset the phone.
  2. Upload the adapter firmware.
  3. Reprovision the phone to GazelleTel servers.

Cause

This is a known issue with the Yealink WiFi adapters (WF40).