pavucontrol missing device selection per stream after upgrade from Debian 8 to 9

["mikesa@corigroup.it" <mikesa@corigroup.it>]

This is my current pavucontrol, on Debian 9: https://imgur.com/a/5S5OLme
while this was what it looked like on Debian 8: https://fedoramagazine.org/wp-content/uploads/2015/07/pavucontrol.png

I'm missing the ability to select an (hardware) output for each audio stream
so all audio, from all sources, plays thru the same output.

While for example I would like to have mpv audio output to my headphones
and youtube (firefox) audio output to my speakers.

My pavucontrol version is 3.0-3.1
and my pulseaudio version is 10.0-1+deb9u1

Any idea how to restore those 'advanced' controls on pavucontrol ?


Thank you,
Mike