Turning Sound On and Off
Web browsers prevent audio from automatically playing unless users explicitly turn sound on. In Apporto, you can turn sound on and off using the sound icon in the menu bar.
Unmute/Mute
Click the sound 
icon in the top panel to turn sound off.
Click the sound 
icon again to turn sound back on.
In addition to turning sound on in Apporto, sound must also be enabled on your device and in the application (eg. YouTube) in order to hear sound when working in Apporto.