(PulseAudio) Make Built-in Audio Analog Stereo loop another device

Question

TLDR: How do I make Build-in Audio Analog Stereo loop another output device?

I want to isolate some sounds from my computer to only record those, but I want to still be able to hear everything.

TeamSpeak ═════╦════> Built-in Analog Audio Stereo
               ^
Game ══════════╩════> OBS

Game Audio goes to Build-in Analog Audio Stereo and my OBS Output Device

TeamSpeak only goes to Build-in Analog Audio Stereo

I can already change the program's device in PulseAudio, I just need to route my obs Output Source to my Built-in Analog Audio Stereo Source

Answer 1

So you want a new sink that can be selected for Games, which forwards to two other sinks.

Create a null sink:

pacmd load-module module-null-sink sink_name=games sink_properties=device.description=Games

and add two loopbacks from the monitor output of that sink to the sinks you want:

pacmd load-module module-loopback source="games.monitor" sink="name_of_built_in_stereo_sink"
pacmd load-module module-loopback source="games.monitor" sink="name_of_obs_sink

You can get the names with

pacmd list-sinks | grep name:

and omit the angular brackets.

Try on the commandline first, then add to Pulseaudio initialization files when it works the way you want.