Before following the steps below, try restarting your web browser.

Check your Volume Settings

Windows:

Speakers: Click on speaker icon → Make sure un-muted and set volume to about half

Right click speaker icon → Click Playback Devices

Check default audio device. If you are not hearing sound, click on the icon of your preferred speaker device, and click "Set Default", restart Chrome, and try again.

Microphone: Right click speaker icon → Recording devices

Check your default device. If it is not correct, select the correct one and press "Set Default" and try again.

In the same panel, left click on the Microphone you have selected, and click "Properties" and ensure it is not muted.