If there are audio or connectivity issues with your Yealink headset there are some steps to go through to enable and streamline the returns process. This means a faster turn around for returned items and if a device is already declared as RMA by Yealink then replacements can be sent straight away.
Device update
Make sure device firmware is up to date by connecting to a PC, running the Yealink USB Connect software. Detailed instructions as per Yealink KB: https://support.yealink.com/en/portal/knowledge/show?id=60d47356076300004a00709d&title=2.%20How%20to%20Update%20the%20Firmware%20for%20My%20Device%20Using%20Yealink%0AUSB%20Connect%3F
Confirming the fault and data collection
To rule out external factors confirm the issue(s) still occur against a different phone or PC.
If the issue remains on a different device collect the diagnostic files and generate a support ticket with Yealink as per this guide: https://support.yealink.com/en/portal/knowledge/show?id=60d47356076300004a007095
Excerpts from the links above:
How to Update the Firmware for My Device Using Yealink USB Connect?
Prerequisites
The firmware version of Yealink USB Connect should be 0.32.69.0 or higher.
Procedure
1.) Run Yealink USB Connect.
2.) Go to Update device.
3.) Do one of the following:
a)Click Check for updates to automatically update the firmware to the newest version.
b)Click Update manually to update the firmware to the specific version manually.
4.) Confirm the action.
You need to download the firmware on the product documentation page first.
How to Report the Issue to Yealink?
For headset issues, click the link below and fill out the form. Next, you can open up the Yealink USB connect to get your firmware version. Then type a description of your problem and submit it. It will then ask for your contact information, including your email address. Yealink will typically respond within 24 hours.
https://ticket.yealink.com/page/create-ask.html
How to Collect Diagnostic Files?
Yealink DECT WH6x headsets support two types of diagnostic files (including log files and audio files) to help analyse the headset problem. You can export these files at a time via Yealink USB Connect Tool and troubleshoot if necessary. The diagnostic file format is **.zip.
Steps:
1) Make an audio call, and go to the YUC path: Device support -- Comprehensive Diagnosis, select Audio collection and Collect operating system logs, then click Start.
2) Then try to reproduce the audio issue again. After the audio issue is reproduced, please click Stop to export the diagnostic files(audio and log files).