Pulse Audio

show commands available in pacmd
pacmd --help
info on PulseAudio deamon
pactl info
list loaded modules
pacmd info
list available devices
aplay -l
aplay -L
pacmd list-cards
To list existing streams
pactl list sink-inputs
pactl list source-outputs
moving application to another sink (sound output) while it is running
pacmd move-sink-input [id to move] [destination sink id]

Further reading