<p>If the focused app does not have a volume control you can pick your desired behavior</p>
<ul>
<li>Previous App - the focused app will be the last app that had a volume control</li>
<li>System Sounds - switch to control system sounds. For example, if you're using an app that makes a windows "error" sound, its volume is controlled by system sounds. So you can adjust the error sound without impacting other apps</li>
<li>Main System Volume - switch to the main volume control for the system. This will change the volume of all apps</li>