Press the MUTE button or the volume control button to see if the sound is muted or to check the volume level.
Reinstall the sound driver.
The Volume window may look different depending on the model.
Select the Start button [
] > [All Apps] > [Windows Tools] > [Control Panel]
> [Sound].
Select the [Recording] tab, then select the microphone area and click Properties.
Select the [Level] tab and adjust the volume.
Check if the microphone is properly connected to the MIC port on the side of the notebook PC.
In the Volume Control menu, uncheck Mute and set the volume to a proper level.
Select the Start button [
] > [All Apps] > [Voice Recorder], press the Record button to see if you can see the wave pattern.
If settings cannot be made normally, check the audio driver and reinstall it by using LG Update & Recovery (or LG Update).
If the problem persists, check if the microphone is working properly.