Hello Nige!
I see you are using windows 10 on your computer.
Here is a guide with pictures http

/www.howto-connect.com/windows-10-raise-the-mic-volume/
[strike]Would[/strike] Should that not work, you can try the following steps:
1) click on [sound] (in the control panel)
2) Manage Audio Devices
3) Click [Recording] Tab
4) right click on the default microphone
5) Click on [Properties ] button
6) Click on [levels] Tab
7) Adjust microphone level to 80
8) Adjust microphone boost to +20 dB
Cheers!