No audio with Gateway M320x (Intel 82801DB-ICH4 with AD1981B

I have done a fresh install of 11.0 on this Gateway M320x, and have not been able to get my sound working from either the built-in speaker or the headphone jack. I have gone through the steps listed in the SDB:AudioTroubleshooting page, and there has been no affect. Some of my configuration details are below:

:~> cat /proc/asound/version 
Advanced Linux Sound Architecture Driver Version 1.0.16rc2 (Thu Jan 31 16:40:16 2008 UTC).
:~> cat /proc/asound/modules
 0 snd_intel8x0
:~> cat /proc/asound/cards
 0 [I82801DBICH4   ]: ICH4 - Intel 82801DB-ICH4
                      Intel 82801DB-ICH4 with AD1981B at irq 10

The contents of my /etc/modprobe.d/sound file:

options snd slots=snd-intel8x0
# W60f.wxMdEc9vFX5:82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) AC'97 Audio Controller
alias snd-card-0 snd-intel8x0
options snd-intel8x0 enable=1 index=0

Found the problem in another forum, can’t remember the page now. I needed to go into alsamixer and turn the External Amplifier off, everything came on instantly then.

Great! Congratulations, and thank you for sharing your solution. A number of different thinkpad model laptops also have this problem.