Have you tried using the headphones with another computer? If the microphone works fine with other computers, please update the audio drivers and then check. If you have difficulty finding the audio drivers, please reply with the Device Instance ID of the sound card. To get the Device Instance ID:
1. Press and hold the Windows Key and then press the R key on the keyboard to launch Run Dialog Box.
2. Type "devmgmt.msc" and hit "Enter".
3. Expand "Sound, video and game controllers" and check what device is listed here. If the sound card is not listed here, expand the "Unknown Devices"/"Other devices" and check.
4. Double click the listed Audio Card.
5. Click the "Details" tab.
6. Select Device Instance Path or Device Instance Id (whichever is available for your version of Windows) from the drop down box.
7. Make a note of the Device Instance Path or Device Instance ID and add this in your reply.
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