SUCCESS! [was Re: Setting up a microphone]

[Angus Leeming]

Angus Leeming wrote:

> Can anyone offer any advice on how to get my microphone working on a
> Fedoda Core 3 machine with a SiS SI7012 sound card? Sound output is fine,
> but I have no input at all.
> 
> The microphone is a cheapo telephony headset plugged into the single
> (pink if that matters!) mic port. Everything works well if I reboot the
> machine under Windows.
> 
> I'm using the KDE frontend to FC3 rather than the Gnome equivalent.
> krec records as expected from the out_soundcard.
> 
> I've fired up kmix and "unmuted" it. Volume level is "high".
> aRts is in full-duplex mode.
> 
> However, when I attempt to record to krec, the VU-meter remains
> obstinately unresponsive.
> 
> Any clues for a sound-newbie?
> Angus

I can report success and how I achieved it although why it works is beyond
my knowledge!

I set IGain to some reasonably high value and mic volume to zero as this
just feeds input to output:

$ aumix -q
vol 100, 100, P
pcm 71, 71
speaker 0, 0
line 0, 0, P
mic 0, 0, R
cd 0, 0, P
igain 80, 80
line1 0, 0, P
dig1 100, 100
phin 0, 0, P
phout 0, 0, P
video 0, 0, P

kmix reports that "Capture" is on. This is aumix's igain entry.

The magic is in alsamixer. The trick is to turn OFF "Mic As Center/LFE"

| Card: SiS SI7012
? Chip: Realtek ALC650E
? Item: Mic As Center/LFE [Off]
?
?            ------    CAPTUR                               ------
?    ????     ?MM?     L?MM?R    ?MM?     ?MM?               ?MM?
?    ?  ?     ?  ?      ?  ?     ?  ?     ?  ?               ?  ?
?    ?  ?     ?  ?      ?  ?     ?  ?     ?  ?               ?  ?
?    ?  ?     ?  ?      ?  ?     ?  ?     ?  ?               ?  ?
?    ?  ?     ?  ?      ?  ?     ?  ?     ?  ?      Mic1     ?  ?
?    ?  ?     ?  ?      ?  ?     ?  ?     ?  ?               ?  ?
?    ?  ?     ?  ?      ?  ?     ?  ?     ?  ?               ?  ?
?    ?  ?     ?  ?      ?  ?     ?  ?     ?  ?               ?  ?
?    ????     ????      ????     ????     ????               ????
?             0<>0        0                                  0<>0
?  Line-In     CD       Mic   <Mic As C>Mic Boos  Mic Sele  Video

Hope that this helps someone in the future!
Angus