How to route all Flash-generated sound to the USB headset only when it is plugged in?
In the pavucontrol GUI, it is
not obvious to me how to route all sound
output through the USB headset when it is plugged in. That includes Flash-generated sound inside
Firefox. And it means not to send sound to the physical soundcard
nor to the soundcard hardware on the motherboard. And I would like to do all of that without disabling
things in the BIOS and without requiring physical removal of the
soundcard from the system. And without having to explicitly do anything such as shutdown pulseaudio, or restart anything explicitly myself at the time of invoking Firefox.
I have read the FAQ about simultaneous sound to multiple devices, but that is not really what I want.
Is that possible via pavucontrol or via the PulseAudio CLI?