Thanks Luke. Yes, I installed alsa from Ubuntu Audio Dev PPA when my sound
disappear and it was OK until new Ubuntu update. I solved it in this way:

sudo apt-get purge linux-sound-base alsa-base alsa-utils
sudo apt-get install linux-sound-base alsa-base alsa-utils

Christian

2010/9/20 Luke Yelavich <email address hidden>

> It seems you have updated your alsa drivers from somewhere. If you
> manually compiled the alsa drivers, then I suggest you re-install your
> kernel to replace the drivers with the drivers from the latest lucid
> kernel, i.e re-install the package linux-image-2.6.32-24-generic. If you
> installed updated alsa drivers from the Ubuntu Audio Dev PPA
> https://launchpad.net/~ubuntu-audio-dev/+archive<https://launchpad.net/%7Eubuntu-audio-dev/+archive>,
> then I suggest you
> uninstall this package, to determine whether sound works again. The
> package you want to uninstall is linux-alsa-driver-
> modules-2.6.32-24-generic.
>
> Either way, once you remove the package or re-install the kernel, please
> run the following command in a terminal: apport-collect -p alsa-base
>
> https://bugs.launchpad.net/bugs/643964/+attachment/1615804/+files/CurrentDmesg.txt
>
> Please report back as to whether this helps.
>
>  affects ubuntu/alsa-driver
>  status incomplete
>
>
> ** Changed in: alsa-driver (Ubuntu)
>       Status: New => Incomplete
>
> --
> Soundcard not detected
> https://bugs.launchpad.net/bugs/643964
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in “alsa-driver” package in Ubuntu: Incomplete
>
> Bug description:
> After update (yesterday) suddenly Lucid 10.04.1 LTS not recognize the sound
> card.
> cat /proc/asound/modules return nothing.
> aplay -l return "no sound card detected..." or something like this
> cat /proc/asount/version return:
> Advanced Linux Sound Architecture Driver Version 1.0.23.
> Compiled on Sep 19 2010 for kernel 2.6.32-24-generic (SMP)
> lspci | grep -i audio return:
> 00:05.0 Audio device: nVidia Corporation MCP61 High Definition Audio (rev
> a2)
> 01:0a.1 Multimedia controller: Brooktree Corporation Bt878 Audio Capture
> (rev 11)
>
> ProblemType: Bug
> DistroRelease: Ubuntu 10.04
> Package: alsa-base 1.0.22.1+dfsg-0ubuntu3
> ProcVersionSignature: Ubuntu 2.6.32-24.43-generic 2.6.32.15+drm33.5
> Uname: Linux 2.6.32-24-generic x86_64
> NonfreeKernelModules: nvidia
> AlsaDevices:
>  total 0
>  crw-rw----+ 1 root audio 116, 3 2010-09-20 19:56 seq
>  crw-rw----+ 1 root audio 116, 2 2010-09-20 19:56 timer
> AlsaVersion:
>  Advanced Linux Sound Architecture Driver Version 1.0.23.
>  Compiled on Sep 19 2010 for kernel 2.6.32-24-generic (SMP).
> AplayDevices: aplay: device_list:223: no soundcards found...
> Architecture: amd64
> ArecordDevices: arecord: device_list:223: no soundcards found...
> AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq',
> '/dev/snd/timer', '/dev/sequencer2', '/dev/sequencer'] failed with exit code
> 1:
> Date: Mon Sep 20 20:05:25 2010
> InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
> PackageArchitecture: all
> ProcEnviron:
>  LANG=es_AR.utf8
>  SHELL=/bin/bash
> SourcePackage: alsa-driver
> Symptom: audio
> Title: Soundcard not detected
> dmi.bios.date: 02/05/2009
> dmi.bios.vendor: American Megatrends Inc.
> dmi.bios.version: P1.50
> dmi.board.name: N61P-S
> dmi.board.vendor: ASRock
> dmi.chassis.asset.tag: To Be Filled By O.E.M.
> dmi.chassis.type: 3
> dmi.chassis.vendor: To Be Filled By O.E.M.
> dmi.chassis.version: To Be Filled By O.E.M.
> dmi.modalias:
> dmi:bvnAmericanMegatrendsInc.:bvrP1.50:bd02/05/2009:svnToBeFilledByO.E.M.:pnToBeFilledByO.E.M.:pvrToBeFilledByO.E.M.:rvnASRock:rnN61P-S:rvr:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.:
> dmi.product.name: To Be Filled By O.E.M.
> dmi.product.version: To Be Filled By O.E.M.
> dmi.sys.vendor: To Be Filled By O.E.M.
>
> To unsubscribe from this bug, go to:
>
> https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/643964/+subscribe
>