I've managed to record some samples with parecord on the pulseaudio Pi. As usual, the man page for parecord etc was about as helpful as a chocolate teapot in a sauna, but some flailing around on google eventually found a page with something that worked.

 parecord --channels=1 -d alsa_output.platform-bcm2835_audio.analog-mono.2.monitor testsound.wav

records the output of the headphone socket channel until you ctrl-C. I also tried with the HDMI output in case this is all down to some bug in the headphpone output - which has happened in the past. When playing the two samples I couldn't hear any difference, so I think that saves one level of nightmare.

I'm loathe to dump a meg-and-a-half of horrible noise file in list mail, or indeed on the swiki - so you ought to be able to download from https://mega.nz/folder/iN1wWajL#SkljQIWhHP8c6McE9HDwDg 

Currently there are two files, the Pi4-pulse-1.wav is the noise made by my code snippet plus some waggling of mouse over the normal pianokeyboardmorph, and -2 is waggling the mouse over the scratch note chooser keyboard morph.

I'd add files for the alsa Pi but I can't make arecord work at all. As usual, making sense of a man page is ridiculous.

I've tried a variety -

arecord -d 5 -f cd -D -t wav output Pi4-alsa-1.wav
ALSA lib pcm.c:2565:(snd_pcm_open_noupdate) Unknown PCM -t
arecord: main:828: audio open error: No such file or directory

arecord -d 5 -f cd -D output -t wav  Pi4-alsa-1.wav
arecord: main:828: audio open error: No such file or directory

 arecord -d 5 -f cd  -t wav  Pi4-alsa-1.wav
ALSA lib pcm.c:2565:(snd_pcm_open_noupdate) Unknown PCM input
arecord: main:828: audio open error: No such file or directory

arecord -d 5 -f cd  -t wav  foo
ALSA lib pcm.c:2565:(snd_pcm_open_noupdate) Unknown PCM input
arecord: main:828: audio open error: No such file or directory

arecord -d 5 -D output  -t wav  Pi4-alsa-1.wav
arecord: main:828: audio open error: No such file or directory

 arecord -d 5 -D output  -t wav  ./Pi4-alsa-1.wav
arecord: main:828: audio open error: No such file or directory

 arecord -d 5 foo.wav
ALSA lib pcm.c:2565:(snd_pcm_open_noupdate) Unknown PCM input
arecord: main:828: audio open error: No such file or directory

I even found the arecord.c sources and looked for the error message - of course, there is no reasonable way to work out what file is not there...

Advice on a suitable command most welcome.

tim
--
tim Rowledge; tim at rowledge.org; http://www.rowledge.org/tim
Strange OpCodes: BBL: Branch on Burned out Light