[Alsa-user] snd_ice1712 ADC-sliders disappeared

[Klaus B. <bb...@un...>]

Hello.

I do remember, that a long time ago the env24control for my M-Audio
Audiophile 2496 was showing two ADC-sliders ("ADC 0" and "ADC 1") right
beside the two DAC-sliders in the "analog volume"-section. Some while
ago (I can't exactly recall when) these ADC-sliders disappeared. Only
the ADC-sliders are left. They also are not listed anymore in the output
of "amixer", so this must be ALSA-related and not a problem of
envy24control. Please also note that internet-searches for 'ice1712
"Simple mixer control 'DAC',0"' also give several results. I did this to
proof that i remembered correctly about the DAC-sliders existence. ;)

First i thought there is something wrong with my Gentoo-configuration.
But i tried to boot Knoppix 6.4 and there the sliders are not present,
too. So now i wonder if they have been removed from the drivers with
some update.

I could imagine that some developer thought that they are redundant as
there are also "H/Win 1/2"-sliders. However these IMHO behave a little
different. To explain it i have to get into some detail:
 The 2496-card has an internal hardware-mixer, which allows you to route
any input-channel to any output-channel. If i assign this digital-mixer
to "H/W Out 1/2" in the "Patchbay/Router" then i can control the analog
input-signal over the "H/Win 1/2"-sliders.
 When i disable the mixer by routing "H/W In" directly to "H/W Out" then
the "H/Win 1/2"-sliders do not have any effect. Thus the sliders control
the volume of the signal that is sent to the digital-mixer. Not the
input-signal in general. However in opposite to this the DAC-slider
still does affect the output-signal - even with the input routed
directly to the output.

The reason why i think that the ADC-sliders still are needed is that at
the moment i have no way to control recording-volume in Audacity. No
matter if i disable or enable the internal digital-mixer and no matter
if i fully rise or lower the sliders, I always get a recording-signal in
Audacity which is at maximum. I would expect to be able to control this
over the ADC-sliders.

I'm not sure if this is a bug or if i am misunderstanding something here
and i am not sure if this is the right place for this issue, but i hope
that someone can either help me or tell me where i should report this issue.

Thanks for reading.