[alsa-devel] Verifying mixer dB data/Invalid dB data from USB cards, especially Aureon 5.1 MkII

Raymond Yau superquad.vortex2 at gmail.com
Sun Feb 28 08:32:12 CET 2010

2010/2/24 Lennart Poettering <mznyfn at 0pointer.de>

> On Tue, 23.02.10 12:47, Raymond Yau (superquad.vortex2 at gmail.com) wrote:
> Are you suggesting that on all drivers the the index part of a
> snd_mixer_selem_id_t directly relates to the subdevice id of a PCM
> stream on the same card? Is that true? Jaroslav, Clemens, Takashi, can
> you say something about that?
> (tbh I find that very unlikely, given that the device index would not be
> encoded then)
> Lennart
Those are the per voice volume control of the hardware mixing sound card

This is a little bit different from the pulse pre-application volume control

It seem that pulseaudio allow the application open only one audio stream ,
but this per voice volume control allow application to open more than one
audio stream

e.g. Skype need to play the human voice and the ringing bell and it have to
open two audio streams using either two hw devices or dmix

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