When a USB headset microphone does not work, select the headset as the computer's audio input and confirm that the chat application uses the same device. Logitech recommends checking microphone volume in the relevant settings rather than raising speaker playback volume.

Inspect mute state on the headset, operating system and application, since any one can block the outgoing signal. Connect directly to another USB port if necessary, avoiding hubs and extensions during testing. This isolates recording selection and connection behaviour without assuming that audible headphones prove the whole headset is configured correctly.