Tweaks
Controlling Audio Devices
Pavucontrol is one of the most well-known audio managers for PulseAudio.
Music playback
In Playback tab, here is a list of all apps that are using your audio system. To mute all System sounds, press the speaker icon in System Sounds. You can also drag the audio slider to adjust the audio.
But, this tab only shows applications currently using audio. Like in this example, I was listening to Spotify.
Recording adjuster
In Recording tab, there is a list of all the programs currently recording audio. It is also possible to mute the recording just by clicking on the speaker icon.
Speaker & Mic level
To make a device default press the lock button. In Output Devices tab, there is a list of all the audio playback devices.
In Input Devices tab, there is a list of all the recording devices.