linux sound

ubuntu 8.04没有声音：

1。播放软件可以打开声卡，lspci，lsmod检查得到声卡芯片－>声卡驱动没问题；
2。打开音量控制器，软硬件调大声音，还是没声音；
3。自测试，cat /dev/audio > /dev/audio，也没听到说话声；
4。打开alsamixer，发现很多功能都没开启；逐一开启（每一项按m，利用方向键调强度）；－>可以听音乐，录音了；

其他人的解决方法：
I have no sound in Breezy, neither system sounds nor music. I have tried quite a few things, but none seem to work.

Please contribute any hunch you have on my situation, I might help me solve my problem and finally get rid of the hated mainstream os I am forced to continue to use.

My Hardware

I have a Toshiba Portege 3490CT laptop. The sound card is an Intel 82440MX. It is recognized correctly, it seems.

dante@inferno:~$ lspci
...
0000:00:00.1 Multimedia audio controller: Intel Corp. 82440MX AC'97 Audio Controller
....

What I Have Tried

1. Opened all the channels imaginable with alsamixer.

2. Checked that I am part of the audio group with id. It would seem that I am.

3. Checked the driver needed: it is the snd_intel8x0, according to the alsa homepage. It appears to be correctly loaded.

dante@inferno:~$ lsmod
....
snd_pcm_oss 0
snd_pcm 3 snd_intel8x0,snd_ac97_codec, snd_pcm_oss
snd_timer 1 snd_pcm
snd 8 snd_intel8x0,snd_ac97_codec,snd_pcm_oss,snd_mixer_ oss,snd_pcm,snd_timer
sndcore 1 snd
snd_page_alloc 2 snd_intel8x0,snd_pcm
.....

4. Fiddled with System -> Preferences -> Multimedia System Selector, swithcing to and from alsa, oss, and esd.

5. I speculated it was an irq conflict, so I tried passing (several attempts) acpi=off, pci=routeirq, acpi_irq_force=5 then 7 then 9 (all should be free according to my bios) in the grub menu.lst.

6. Blacklisted the oss drivers in /etc/hotplug/blacklist, speculating they might conflict with the alsa drivers. Also tried to take snd_intel8x0m out of the blacklist (it is blacklisted by default).

7. Tried the

8. Temporarely replaced the hdd with one with Windows on it. The hardware works.

9. Googled madly, to no avail.

Clues that something is wrong

Although the system apparently seems to recognize the sound chip and to load the driver module correctly, there are several subtle malfunctionings which might give you a clue on what's wrong with the setup.

When I fiddle with System -> Preferences -> Multimedia System Selector, the Pipeline Test in Default Source hangs my laptop.

At bootup, the various modules are loaded and respond with "ok" before passing to the next stage. Hotplug though does not respond with "ok", the system just skips through to the next stage.

Also, blacklisting a module does not always work.

As you might notice, the output of lsmod says that there are 8 snd modules, but it lists only 6.

用“ asoundconf  list ”列出声卡型号，然后“ asoundconf set-default-card   Intel" 后面的Intel为上一步列出的声卡型号。

点开音量控制，打开“编辑”－－“首选项”，在里面选择surround，声音出来了。