ThinkPad microphone not working

[suvayu ali]

Hi Stan,

On Sun, Apr 15, 2012 at 20:05, stan <gryt2 at q.com> wrote:
>
>> F15 Live USB: <http://pastebin.com/VkA33cD8>
>> F16: <http://pastebin.com/TZm4XS4d>
>
> I saved the files and ran a diff.  There are *major* differences for
> your device from F15 to F17!  And in the environment.
>
> The settings difference I noticed at the time you captured these, and
> that might have an effect on your situation, F15 <, F16 >
>
>> Simple mixer control 'Internal Mic',0
> 543,548c596,604
> <   Front Left: Capture 80 [100%] [6.00dB] [on]
> <   Front Right: Capture 80 [100%] [6.00dB] [on]
> < Simple mixer control 'Analog Mic Boost',0
> <   Capabilities: cenum
> <   Items: '0dB' '10dB' '20dB' '30dB' '40dB'
> <   Item0: '20dB'
> ---
>>   Front Left: Capture 0 [0%] [-74.00dB] [off]  <-- mic turned off?
>>   Front Right: Capture 0 [0%] [-74.00dB] [off]
>> Simple mixer control 'Internal Mic Boost',0
>>   Capabilities: volume penum
>>   Playback channels: Front Left - Front Right
>>   Capture channels: Front Left - Front Right
>>   Limits: 0 - 4
>>   Front Left: 3 [75%] [36.00dB]
>>   Front Right: 3 [75%] [36.00dB]
>
>

You are correct! I somehow didn't understand what the output said until
you pointed it out. :-p

I finally figured out what is going wrong. The "Internal Mic" is turned
off, as you observed, when I turn it on and raise the volume, recording
works. But this does not survive a reboot. So I thought maybe its the
state file that is causing this. So I deleted it, fixed the settings
with alsamixer, then stored the state with "alsactl store". I confirmed
the state file has the correct settings, and yet it still does not
survive a reboot! So I checked the state file again, and strangely it
has the correct settings! So for some unknown reason the state file is
being ignored. I can fix this by executing "alsactl restore".

For the moment this is an acceptable workaround, but this made me think;
the error I mentioned earlier in the thread,

  pulseaudio[1455]: module-alsa-card.c: Failed to find a working profile

probably indicates to this issue. Would you agree? Does this seem worthy
enough for further investigation?

Your suggestions were very helpful throughout this thread. And I became
a lot more familiar with alsa in the process. Thank you very much. :)

Cheers,

-- 
Suvayu

Open source is the future. It sets us free.