In Windows 10, having an Audio Recording device (microphone or DAX TX) lets you use PC AUDIO and DAX to send audio to your FLEX-6000. Win10 has added a privacy setting that prevents audio recording devices from accessing your PC. Windows can disable the Audio Recording devices, especially after a Windows Update which prevents PC AUDIO, DAX TX and third-party digital mode applications, like WSJT-X from working properly.
To enable the Audio Recording devices, do the following.
Open Settings (Windows Key+I ) > Privacy > Microphone
Set allow access to the Microphone on this PC by finding the Allow apps to access your microphone section and turn it ON
If your PC has updated to the 1903 Feature Update, there is one other setting that needs to be changed. Fine the Allow desktop apps to access your microphone section and turn it ON