A: 

1. If you pair the headset via Bluetooth, the mute button will only work when you have cell phone calls instead of desk phone calls or calls from apps, websites, or software on a phone or computer.

2. If you pair the headset with your computer via Bluetooth, you cannot mute calls from the computer.

3. If you pair the headset with your computer via the dongle successfully, you can mute calls like Skype. 

If you pair the headset with your computer via the dongle but you can still not mute/unmute:

1) Reset the headset: When the headset is on and not occupied by a current call, press the MFB and Volume - buttons at the same time and hold for 5 seconds to clear the pairing record.

 Turn off and turn it back on, guaranteeing the headset is in pairing mode (Red and blue LED flash alternately).

2) Unplug the dongle and plug the dongle into a different USB-A port. Please guarantee there is an LED light on the dongle.

3) Try to pair again and make sure the KH122M headset and dongle are paired successfully. You can listen to music to test it.

4. Kindly note that the headset can only mute/unmute itself instead of the computer, which means you can mute the headset's microphone when pairing via the dongle. The headset will

 announce “Mute on/off ”. The call will be muted/unmuted, but you can notice that the Mute icon (microphone icon) of the UC platform you are using (take Zoom as an example) status on the

 computer has not been changed. The headset can only control itself instead of the computer, so if you check “Mute my mic when joining a meeting” in the settings of your Zoom meeting

 to mute yourself by default for each Zoom meeting, the headset cannot unmute it. Please click the Mute icon (microphone icon)  in the bottom left corner to unmute your audio. If you unmute

 yourself by clicking the Mute icon (microphone icon) in the bottom left corner of your computer to mute your audio, the headset cannot unmute it. Please click the Mute icon

 (microphone icon) in the bottom left corner of your computer to unmute your audio, which is the same with almost all headsets on the market now unless the headset is certified for the platform you are using (like Microsoft Teams certified), 

but even if it is certified for a specific platform you are using, the headset is not fully functional for all other UC platforms on the computer, which means most headsets on the market are not fully functional when pairing with a computer.

If you really mind the problem, please don’t hesitate to contact us via service@prancybt.com to ask for a refund, even if the Amazon return window is closed or the product package is missing. We will

assist you within 24 hours to save you time and money.