Digitus DA-12003 Guía Rápida De Instalación página 3

Windows
Go to Control Panel > Sound and check that the USB PnP Sound
Device is set as the default device in both the Playback and
Recording tabs.
macOS
Go to System Preferences > Sound and check that USB PnP Sound
Device is set as the default device in both the Input and Output tabs.
The USB headset can control the output volume of your computer
using the volume up and down buttons and can completely mute
audio output via the headphone mute button. It is possible to
monitor the level that the computer is set to by hovering the mouse
over the speaker icon in the system tray in Windows, whilst macOS
will show the volume adjustment on screen with each button press.
It is also possible to mute just the microphone by using the
microphone mute button. A red LED will illuminate on the controller
to signify that the microphone is muted.
Under normal operation the green LED will flash, if it is permanently
lit please adjust the microphone level:
Windows > Control Panel > Sound > Recording > USB PnP Sound
Device > Properties > Levels
macOS > System Preferences > Sound > Input > USB PnP Sound
Device > Input Volume
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