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Chapter 8. Hardware |  |
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Chapter 8. Hardware | |
In the graphical desktop the audio output as for HDMI, 3.5mm Jack and USB Audio device can be selected using the speaker icon. There is also a mic icon where the microphone source can be selected as from the USB device.
USB audio devices are automatically detected.
aplay -l or cat /proc/asound/cards to see what is there
aplay -D hw:2,0 /usr/share/sounds/alsa/* will speak or fail with a channels error. This might be due to mono files and the device does not support this. file /usr/share/sounds/alsa/*.wav confirms this. In this case use the alsa plugins aplay -D plughw:2,0 /usr/share/sounds/alsa/*
arecord -d 3 -f cd -D hw:2,0 test_rec.wav it might also have a format issue with -f cd
arecord -d 3 -f cd -D plughw:2,0 test_rec.wav will work
However it is also possible to record the way the hardware can do it.
cat /proc/asound/card2/pcm0c/info shows about the card and
arecord -D hw:2,0 --dump-hw-params /dev/null shows what it supports as S16_LE for the microphone attached to the USB audio device
arecord -d 3 -D hw:2,0 -f S16_LE -c 1 -r 44100 test_rec.wav
aplay -D plughw:2,0 test_rec.wav
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