1) Right click on the live view of the camera and select "edit".
2) Under the microphone option click on the small 3 dots as below.
3) Select "new" from the menu that appears.
4) Next click the arrows as below:
5) Select the correct audio device from the drop-down menu:
6) Select ok and then finish.
7) Finally, make sure you have audio turned on as below:
8) The only other thing you would have to check is your speaker setup - making sure you have the correct speakers selected.
To do this:
1) Click on the speaker icon at the bottom right hand of the windows screen:
2) Click on the top line to see the selection of your speaker devices.