On Thu, 20 Jun 2019 15:06:59 -0400
Bob Goodwin <bobgoodwin(a)fastmail.us> wrote:
I rarely have computer audio problems, it usually just works. But
today I need to record voice and it does not do anything, pulse audio
shows rear microphone plugged in and the level is turned up. aplay
produces a test sound from the speaker and sound works as expected,
just no mic audio.
Any ideas welcome, Bob
It's a configuration problem. If pulse sees the mic, then alsa has
recognized it.
First thing, run
alsamixer -c <card number>
Then hit F4 to get to the capture screen. Make sure that the capture
is turned on in alsa, and at a high enough level.
Then, if you don't have it installed already, install pavucontrol.
Bring it up and play around with the default settings (last tab) for the
mic until you can see waveforms for capture in the capture tab.
You could instead use arecord to try to capture some sound in a .wav
file. I haven't done that for a long time, so you will have to read the
man page, man aplay, to figure out how if you decide to do so.
Another alternative is to use audacity to capture the sound from the
mic. It also allows configuration for direct record from alsa, I think.
So, you could disable the card in pulseaudio, and use alsa directly if
you just can't get pulse to record.