Microphone no longer working

[Derek Croxton]

My microphone stopped working sometime; I'm not sure exactly when, 
because I don't use it that often, but I first noticed it yesterday. 
Sound plays fine. The mic is hard to test because gnome-sound-recorder 
crashes (segmentation fault) when I try to record, and Audacity gives me 
the "can't open input device" error. (I noticed the problem when I tried 
to use Gizmo.)

In accordance with the "Comprehensive Sound Problem Solution Guide," I 
have done the following:

     * Checked that the microphone is not muted and has volume up
     * Re-installed linux-sound-base, alsa-base, and alsa-utils
     * Tried to recompile the drivers from the ALSA project, but got errors

I've also tried with and without esd and jack running. I have an 
intel8x0 chipset soundcard, with an mpu401 chipset also on a Hauppauge 
tv capture card. (I've never had a problem with the sound getting mixed 
up between the cards before.) Here is what I get from "arecord -l":

**** List of CAPTURE Hardware Devices ****
card 0: I82801DBICH4 [Intel 82801DB-ICH4], device 0: Intel ICH [Intel 
82801DB-ICH4]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
card 0: I82801DBICH4 [Intel 82801DB-ICH4], device 1: Intel ICH - MIC ADC 
[Intel 82801DB-ICH4 - MIC ADC]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
card 0: I82801DBICH4 [Intel 82801DB-ICH4], device 2: Intel ICH - MIC2 
ADC [Intel 82801DB-ICH4 - MIC2 ADC]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
card 0: I82801DBICH4 [Intel 82801DB-ICH4], device 3: Intel ICH - ADC2 
[Intel 82801DB-ICH4 - ADC2]
   Subdevices: 1/1
   Subdevice #0: subdevice #0

I'm a bit puzzled by the presence of two entries for microphones. It 
doesn't make any sense to me, but maybe it is some technical thing that 
I don't understand. When I run alsamixer (but not alsamixergui or the 
gnome alsa mixer), there is a column labelled "Mic Sele" that shows 
"Mic2" above it; I haven't figured out how to change it.

I tried to test recording using arecord, but nothing happened (the file 
was not even created). I figured this might be because I didn't specify 
a device, but I couldn't figure out the name of the microphone devices 
revealed in "arecord -L".

As always, any help is appreciated. It's almost more frustrating that it 
used to work fine, since I know there is some configuration thing I can 
change to make it work, I just don't have any idea what it is.

-- 
Sincerely,
Derek