[pulseaudio-discuss] Conexant CX20585 recording does not work

[Colin Guthrie]

'Twas brillig, and Gabriel Schulhof at 07/03/11 19:56 did gyre and gimble:
> Hi!
> 
> My mom has a laptop with the following sound card:
> 
> lspci: 00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA)
> (rev 40)
> 
> driver: snd_hda_intel
> 
> alsamixer:
> Card: HDA ATI SB
> Chip: Conexant CX20585
> 
> I can't record from this card no matter what I try. It seems that
> alsamixer has a lot more options than pulseaudio:
> 
> Mic B            <Capture switch>
> Mic C            <Capture switch>
> Mic E            <Capture switch>
> Mic F            <Capture switch>
> Capture          <0% -- 100% slider>
> Analog Mic Boost <0 db -- 40 db slider with 10 db increment>
> 
> Nevertheless, I will attach the output from pacmd list-sources.
> 
> I have tried to record from each mic in turn, I have tried the different
> boost levels (0 db - 40 db), but I have had no luck picking up anything. I
> have attached an external mic to the line-in, but no difference.
> 
> When I say "I have tried to record" I mean that I logged into her
> computer, chose one of the mics from the above list, and then I told my
> mom to say something while looking at the input sound level indicator in
> the GNOME sound settings panel. On other computers, I have found this a
> sufficient indication of whether the mic works.
> 
> Is this inability to record a known limitation of this sound card? If not,
> is there some special setting I have to modify to make it work?
> 
> TIA for your help,

Some mics do this weird out-of-phase thing whereby the recording level
is effectively 0 when the stereo volume is synced. If you set left to
say 5% and right to say 95% then it works fine.

This may be the case with your h/w too.

FWIW The "extra" options you see in ALSA are generally confusing and
useless. PA attempts to consolidate it and make it a lot more user friendly.

Normally you'd get a list of several "port" selectors in
gnome-volume-control. Sadly as your card uses the incredibly helpful
names of "Mic B" through "Mic F" these do not match the various
"standard" names we probe for.

David, have you come across this model on your travels? Any ideas on how
we could best support it?


Gabriel, if the mono trick does not help (and the model= argument to the
HDA alsa module (as suggested by Dark Shadow) does not yield any results
either) perhaps try using alsamixer -c0 to flip those various Mic B
through F to see if any of them make things work?

Cheers

Col

-- 

Colin Guthrie
gmane(at)colin.guthr.ie
http://colin.guthr.ie/

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