I've installed Alsamixer from Google Play.
Gadget is Samsung Galaxy S3.
It has one soundcard (indexed as 0), and 4 devices (0-3).
The device list (from /proc/asound/devices) is the following:
0: [ 0] : control
16: [ 0- 0]: digital audio playback
17: [ 0- 1]: digital audio playback
18: [ 0- 2]: digital audio playback
19: [ 0- 3]: digital audio playback
24: [ 0- 0]: digital audio capture
25: [ 0- 1]: digital audio capture
26: [ 0- 2]: digital audio capture
27: [ 0- 3]: digital audio capture
33: : timer
So pcms list from /dev/snd is
crwxrwxrwx system audio 116, 0 2014-01-16 12:56 controlC0
crwxrwxrwx system audio 116, 24 2014-01-16 12:56 pcmC0D0c
crwxrwxrwx system audio 116, 16 2014-01-16 12:56 pcmC0D0p
crwxrwxrwx system audio 116, 25 2014-01-16 12:56 pcmC0D1c
crwxrwxrwx system audio 116, 17 2014-01-16 12:56 pcmC0D1p
crwxrwxrwx system audio 116, 26 2014-01-16 12:56 pcmC0D2c
crwxrwxrwx system audio 116, 18 2014-01-16 12:56 pcmC0D2p
crwxrwxrwx system audio 116, 27 2014-01-16 12:56 pcmC0D3c
crwxrwxrwx system audio 116, 19 2014-01-16 12:56 pcmC0D3p
crwxrwxrwx system audio 116, 33 2014-01-16 12:56 timer
alsa_aplay can playback sound ok, but when i try to record it records only noise or emptiness.
By experiments i found out that sound can be only 'recorded' with 3-rd device, so the call is:
alsa_aplay -C -D hw:0,3 -r 44100 -f S16_LE -c 1 -d 2 /foo.wav
when hw:0,1 or other is specified i get "pcm_read: read error: invalid argument".
We tried different sampling rates and other arguments.
The same thing happens when i try to record with C-code (jni).
With devices 0-2 it has run-time errors.
With device 3 in pcm_read function it infinitely records emptiness.
We use tinyalsa.
Also i tried to manage the devices from Alsamixer app list, i've set most of them into 100% (don't know which stays for the recorder, so set all) but no effect.
Thanks for your response.
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