pactl

Control a running PulseAudio sound server. More information: https://manned.org/pactl.

• List all sinks (or other types - sinks are outputs and sink-inputs are active audio streams):
  pactl list {{sinks}} short
• Change the default sink (output) to 1 (the number can be retrieved via the list subcommand):
  pactl set-default-sink {{1}}
• Move sink-input 627 to sink 1:
  pactl move-sink-input {{627}} {{1}}
• Set the volume of sink 1 to 75%:
  pactl set-sink-volume {{1}} {{0.75}}
• Toggle mute on the default sink (using the special name @DEFAULT_SINK@):
  pactl set-sink-mute {{@DEFAULT_SINK@}} toggle