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.