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'
Set both your 'Output' and 'Input' devices to your preferred headset...
Go into Genesys Cloud application, then click on profile icon, then 'Preferences'.
Disable all of the Advanced Microphone Settings on the Mini-widget window. It also opens when Salesforce opens, as a separate pop-up window.
