Ubuntu 9.10 Microphone No sound solution

1, look at your sound card chip model
Under the terminal: Head-n 1/proc/asound/card0/codec*
Get model Realtek ALC888
As shown in the figure:

2. Under the terminal: zless/usr/share/doc/alsa-base/driver/hd-audio-models.txt.gz
Find the list of alc883/alc888 chips, there are many models below, choose acer-aspire-4930g here, copy down.
As shown in the figure:

3. Edit ALSA Configuration
Under the terminal: sudo gedit/etc/modprobe.d/alsa-base.conf
At the bottom of the file, add options Snd-hda-intel model=acer-aspire-4930g
As shown in the figure:

4, save, restart.
5, in the Voice preferences to select the appropriate equipment.
As shown in the figure:

Note: 1, notebook model: ACER 4740G 332g32mn os:ubuntu 9.10 Core: 2.6.31-20-generic
2. Article quoted from: Http://blog.csdn.net/netcookies/archive/2009/12/10/4976319.aspx
3, after May 1, the OS has been upgraded to the 10.04 kernel: 2.6.32-22-generic, in this way, can still solve such problems.

PS: The key is alsa-base.config that part, this part of the election is the most critical.

My Lenovo Zhaoyang e46l sound card Codec is: Codec:idt 92hd81b1c5, in that file can not find the corresponding. Refer to this man's method below:

The audio decoder used by the

HP dv4 dv5 dv7 is IDT 92hd71b7x (8.10 sound card is identified as STAC92XX).
My Compaq Presario CQ45-203TX is the same,
in 8.04, the performance of the audio at the end of the last infinite repetition, login completely silent, 8.10 for the infinite repeat sound end.

First
$ head-1/proc/asound/card0/codec#0
To determine if the sound card is IDT 92hd71b7x
Conclusion Naturally is
Codec:idt 92hd71b7x
Otherwise ... ... Please continue to Baidu or Google ...

and then
$ sudo gedit/etc/modprobe.d/alsa-base
at the bottom with one line of
Options Snd-hda-intel Enable_msi=1
Save.

Then restart
$ sudo reboot
(you can also try to restart Alsa
$ sudo alsa force-reload)

should have a sound, otherwise double-click the volume icon to see if there is no mute. This may be a problem with the volume control (too sensitive-)
Last
System--> Preferences--> Audio
The bottom of the device is changed to HDA Intel (ALSA Mixer), with the mouse click "PCM" in the list below to determine.
This volume control is not so sensitive, with the volume key to the bar ~ but still be careful not to zero the PCM, otherwise it will be ... weird noise ...
(Note: This method is also available in Ubuntu 8.04.) )