How can I access the external microphone with Ubuntu?

Question

Sound in Ubuntu, it has its own special joy. I would like my external microphone to work.

Symptoms:

• I can play sound through the speakers
• I can play sound through the headsets.
• Plugging and and plugging headphone output correctly switches.
• I can record from the built-in microphone, using "Sound Recorder" and others.

but:

• I cannot record from the external microphone.
• My Sound Preferences/Input panel has no option for an external microphone.

If the answer is upgrade the ALSA drivers, please say exactly what to type.

Thank you.

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I'm using Ubuntu 9.10 Karmic Koala on a laptop (Gateway W3501), Sigmatel.

That is:

~$ head -1 /proc/asound/card0/code*
==> /proc/asound/card0/codec#0 <==
Codec: SigmaTel STAC9205

==> /proc/asound/card0/codec#1 <==
Codec: Conexant ID 2c06
~$ lspci | grep -i audio
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03)

Answer 1

OK, I found this.

First, I looked at the ALSA website ( http://www.alsa-project.org/main/index.php/Help_To_Debug_Intel_HDA) , because the sound drivers ship out of sync with the usual Ubuntu upgrades. For Intel HDA especially, the recommendation is to install alsamixer and then go playing with settings.

$ sudo get-apt install alsamixer
$ alsamixer

Then I found that the default settings for "Digital Input Source" is incorrect. It should be "Analog".