Verify their Windows Sound microphone device default is set to the headset/microphone:
Right-click on 'speaker icon' in task tray, click on 'Open Sound Settings'
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Set both your 'Output' and 'Input' devices to your preferred headset...
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Go into Genesys Cloud application, then click on profile icon, then 'Preferences'.
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Disable all of the Advanced Microphone Settings on the Mini-widget window. It also opens when Salesforce opens, as a separate pop-up window.
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