Audacity : Record stereo that is playing in browser

[Swamp Thing]

I am running Audacity on a Raspberry Pi 5.

I am following the steps given here https://manual.audacityteam.org/man/tutorial_recording_computer_playback_on_linux.html
trying to record in Audacity a stereo track playing in Chromium browser. This sound is concurrently being sent to a speaker via "USB Audio Device Analog Stereo", whose "monitor" channel outputs the signal that I want.

My problem is that when I go to Pulse Audio Volume Control -> Recording and select USB Audio Device Analog Stereo as my recording source, I see only one single volume slider. The instructions, however, say that two volume controls should appear if stereo recording is working correctly.

In Audacity, I am able to start up a stereo recording track, but both tracks contain the same sound (the sum of the left and right signals from the browser). The single PAVU volume slider controls both their levels.

Am I missing some obscure setup option that needs to be changed? Or is it a basic limitation of Aucacity on the Pi?
My audio hardware is a USB sound device with stereo playback and mono microphone. Is the mono mic configuration somehow forcing Audacity to work in mono, even when the source is not from the USB device? If so, can this be overridden to get stereo?

 

[sbrothy]

Since noone offered any help I’ll just throw my 1 cent in there ….

I’ve had a similar problem setting up MIDI. Have you configured Pulsar to use 2 channels? Cause that is the error message I keep getting.

 

[Swamp Thing]

I will look up more info on pulse config and see if there is something that helps, thanks.