看现象，重启系统，有时候有声音，有时候没声音。
分析，看硬件列表：
varrily@Varrily-Ubuntu:~$ cat /proc/asound/cards
0 [AudioPCI ]: ENS1371 - Ensoniq AudioPCI
Ensoniq AudioPCI ENS1371 at 0xe000, irq 20
1 [V8237 ]: VIA8237 - VIA 8237
VIA 8237 with ALC655 at 0x1000, irq 21
varrily@Varrily-Ubuntu:~$ lspci
00:0a.0 Multimedia audio controller: Ensoniq 5880 AudioPCI (rev 02)
00:11.5 Multimedia audio controller: VIA Technologies, Inc. VT8233/A/8235/8237 AC97 Audio Controller (rev 60)
果然，系统识别了两张声卡。
一张是主板集成的Realtek ALC655
另一张是后来加上去的Ensoniq AudioPCI声卡
很奇怪的是明明在BIOS中禁用了集成的Realtek ALC655，怎么还是出现了？
也许上面的命令只是说明系统有两张声卡，以及所占用的IRQ，或许这就是UBUNTU的特点？？
如何让系统只使用第一块声卡呢？
于是Google一下，看到这样一个方法：
I fixed my Ensoniq 1371 issue buy doing the following:
(please use do not make these changes if your not comfortable doing so)
1. You'll need to edit the “modules” file thru a terminal window.
2. Start you terminal window
3. Once at the flashing prompt type:
4. cd /etc
5. then type
6. sudo nano modules (when asked for the root password please enter it)
# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
lp
psmouse
7. now move your blinking courser to the line just below the list line mine is “psmouse”, yours could be different. then type in “snd-ens1371”, your modules file should look similar to mine:
# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.
lp
psmouse
snd-ens1371
8. To exit and save please do the following:
* Crtl-O
* You'll be asked: “File Name to Write: modules”; just hit the "enter" key.
* next you should see “[ Wrote 9 lines ]”
9. Now it Ctrl-X to exit GNU nano
10. Once that is done you should be back at “/etc$” prompt.
11. Now restart your computer. Once back in Ubuntu test your sound card.
Your sound card should work now, if you have speakers connected to your sound card you should hear the Ubuntu startup sounds. Please let me know if this works for you.
改之，重启，正常！