Updating the Yealink EHS module's firmware is not required in most cases, but newer version do provide support for additional headsets and phone models that have come out after the initial release of the EHS module.
The update process can currently only be done via 3 supported phone models:
Updating the EHS firmware requires you to load a custom firmware to the phone, then using that custom firmware to push the EHS firmware to the EHS adapter via a "Zero Touch" key that normally runs the provisioning wizard. To ensure that the custom firmware remains on the phone on reboot after update, temporarily disable all provisioning options, or contact engineering to ensure that the provided config will not update back to our standard release.
1. Disable provisioning on phone.
2. Upgrade to xx.80.200.1 firmware verison appropriate for phone model.
3. Add "Zero Touch" DSS key.
User interaction required:
1. Press Zero Touch key, then press OK before timer expires.
2. Unplug EHS module (if not already unplugged), then plug it back in.
3. Once the module is recognized, user is prompted to unplug and plug it back in again.
4. Update begins, and takes about 10 seconds.
5. Update complete should appear on the screen. This process can be repeated to visually confirm the new firmware version, or the EHS version can be found on the web UI status page.
4. Re-enable provisioning to return to standard firmware release.