After a few month's tring, I got the sound system working. Here I'd like to share my experience with those friends who are still struggling for sound, and I hope this will offer you some help. (There might be some grammar mistakes, please excuse my poor English ^_^ )
The Linux Sound System is a little bit complicated, so it's not necessary for us to understand in details. Generally, there're a few steps to find out why your system keeps silent.
1 Driver
In most situations, the system's silence is caused by a wrong driver, so first let's check out if the driver is installed properly. To find out what driver should be the correct one, there're two methods.
Open your terminal and type “alsaconf” as root, and the ALSA configuration program will configure your sound system automatically. To get this program, install alsa_utility, alsa_lib, alsa_tools, alsa_driver which can be downloaded from
www.alsa-project.com
Or you can perform this configuration manually:
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Open your terminal and type the command “lspci”
And you'll see some information like
Multimedia audio controller: Intel Corporation 82801DB/DBL/DBM(ICH4/ICH4- L/ICH4-M) AC'97 Audio Controller (rev 03)
If this doesn't work, don't worry, try to find it out under Windows. Right click “My Computer”, click “Properties”, select “Hardware”, then “Device Manager”, and you get the name of the driver told by Windows. Also you'll see other information on the sound card like address, IRQ. Usually, the information provided by Windows should be the same as that provided by Linux, and now I know “Intel 82801DB(ICH4) AC'97 Audio Controller” should be my sound card, and I know it's produced by Analog Devices.
Linux uses modules to drive hardwares. Now let's find out what should be the driver module for our sound card. Visit
www.alsa-project.org
and click the link “Is my sound card supported”, then choose the corresponding vendor (Mine should be Analog Device), then exam the type of your sound card (Mine is AD1819). Now you can see what module should be used (snd-intel8x0 is for me).
Open the terminal and type “modprobe module_name” as root.
It would be nice of your sound card manufacturer to offer the driver for Linux.
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2 Conflict
Conflict makes your system silent though driver is installed properly. Some type of motherboards integrate both sound card and modem, so Linux might mistook the speaker of modem for sound card. Run “lspci” and check out if there is a module with a name very similar to your sound card's name (Like sound_card_module_name+m or sound_card module_name+modem. In my case, I've got snd-intel8x0 and snd-intel8x0m). intel-8x0m should be the module for modem's speaker, and it usually causes the conflict.
Now let's take care of it. Find the module file (Mine is /lib/modules/2.6.22.9-laptop-1mdv/kernel/sound/pci/snd-intel8x0m.ko), and rename it(snd-intel8x0m.ko.bak), or simply add the module into the blacklist so Linux won't load it automatically. Other sound cards might have the same situation. For VIA motherboards, snd-via82xx.ko and snd-via82xx-modem.ko exist.
3 The Mixer
Mixer is a naughty boy, some lap-tops' silence are caused by him. Lap-tops' hardware structure is a little bit different from desktops', so be attention if you're using a lap-top.
Open Kmixer or Alsamixer, you'll see many items there, but not all of them are necessary. Some of these items should be muted. As far as I know, “PCM” and “Master” should be always on.
The method to test which items are necessary is very simple. First, mute all the items, then try to turn them on one by one while playing a audio file, till you get the sound.
That's how I get my sound system working. There is another article on solving problems of sound system. It's written by a Chinese guy who is really experienced.
http://www.linuxsir.org/bbs/showthread.php?t=217259
Tell me if you need to read this article in English, and I'll translate it for you when I finished my study.
Good luck!
I've got the sound
