In previous post I documented the difficulty I was having getting the snd_aloop approach, as given in the user guide, to work on my new raspberry pi 400.
I finally figured out what was going on.
Came across a blog from Raspberry Pi folks posted early 2021 explaining that they had switched from ALSA sound system to PulseAudio, with a few ALSA plug-ins to maintain some compatibility.
Well, snd-aloop is just not supported - the underlying code is just not there.
Instead, you can use the pulseaudio equivalent.
Here is the user-level script I run before firing up wfview and/or wsjtx:
#!/bin/sh
pulseaudio --start
pacmd load-module module-null-sink sink_name=MySinkA
pacmd load-module module-null-sink sink_name=MySinkB
The pulseaudio command starts the pulseaudio server.
The PulseAudio Commands (pacmd) each create an output device with the given name,
together with a corresponding input device (the loop back) called [the given name].monitor
So, for the wfview audio output device, I use MySinkA
and for the audio input device I use MySinkB.monitor
Correspondingly, for wsjtx audio out I use MySinkB
and for audio in I use MySinkA.monitor
No more difficult than the snd_aloop stuff, and it works like a charm.
B.T.W. system does not want pulseaudio server to run as root, so I don’t.
Take care and 73.
=CMP