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UbuntuHelp:SoundTroubleshootingProcedure

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Sound troubleshooting procedure to be followed while creating a single, new question at https://answers.launchpad.net/ubuntu/+addquestion


The Procedure

In order to gather essential troubleshooting information about your sound card, please follow this procedure:

Step 1

Please first try upgrading the ALSA sound system to the newest version. If you are using Ubuntu 9.04 (Jaunty) or Ubuntu 9.10 (Karmic), please use this link

Step 2

Open | Terminal console to get to the command-line. This should launch the gnome-terminal application. In gnome-terminal, click on Edit::Profiles::Edit "Default" profile::Scrolling::Choose "Unlimited" as scrolling option::Close::Close. So make sure that unlimited scrolling is ENABLED in gnome-terminal. Or else it will not be possible to send us the full output from step 3.

Step 3

Please make sure you have rebooted your computer at least once. Then proceed with running the following 2 commands - copy&paste (with the mouse) each command onto the Terminal and then hit <enter> after each command. Tip: If you have a wheel mouse or 3 button mouse, you do not need to type commands into the Terminal. Highlight the command written on the webpage. Move your cursor anywhere in the Terminal and press the wheel or middle button. Automatic Copy and paste! No spelling mistakes! No Typos! No other errors!

wget -O alsa-info.sh http://212.20.107.51/alsa-info.sh 
bash alsa-info.sh --stdout 

Please post the full Terminal output after the script has actually run by creating a new question in launchpad then please copy&paste the terminal output into your newly created question. Carefully inspect the Terminal output of the ALSA Information script that was generated by the previous command

bash alsa-info.sh --stdout

After upgrading ALSA and rebooting the computer please make sure that the ALSA driver version, library version and utilities version are all exactly the same version number. The Terminal output after running the ALSA information script should contain something like this:

  1. ALSA Version
  2. Driver version: 1.0.23
  3. Library version: 1.0.23
  4. Utilities version: 1.0.23

If the Driver, Library and Utilities version numbers are not equal then - in most cases - this is caused by one of the following issues: 1. One of the ALSA components was not successfully upgraded during step 1 in this procedure 2. ALSA was correctly installed or upgraded, but a wrong / old kernel was booted instead of the most recent kernel version. In that case, boot the newest kernel version (that is available in the standard/default Ubuntu repositories) and then retest sound.

For example: if you installed or upgraded to Ubuntu 9.10 (Karmic Koala edition), make sure the running kernel version is 2.6.31-14-generic or higher. Or else sound will not work! For example: if you installed or upgraded to Ubuntu 10.04 (Lucid Lynx edition), make sure the running kernel version is 2.6.32-21-generic or higher. Or else sound will not work!

Step 4

Please copy&paste the following command into the Linux Terminal. Please do not copy&paste this command from an email message into the Terminal, as that will only copy part of the command. The command starts with the command cat and ends with the filter snd. So, please copy&paste the entire command below into a Terminal. Press enter. Then type your normal user password when asked, no stars are given as you type. Then press enter again. Tip: If you have a wheel mouse or 3 button mouse, you do not need to type commands into the Terminal. Highlight the command written on the webpage. Move your cursor anywhere in the Terminal and press the wheel or middle button. Automatic Copy and paste! No spelling mistakes! No Typos! No other errors!

cat /proc/asound/cards; sudo rm /etc/asound.conf; sudo rm -r ~/.pulse ~/.asound* ;sudo rm ~/.pulse-cookie; sudo aptitude install paman gnome-alsamixer libasound2-plugins padevchooser libsdl1.2debian-pulseaudio; aplay -l;  sudo lshw -C sound; sudo lshw -short;ls -lart /dev/snd;  cat /dev/sndstat; lspci -nn;  sudo which alsactl; sudo fuser -v /dev/dsp /dev/snd/* ; dpkg -S bin/slmodemd; dmesg|grep irmware; sudo /etc/init.d/sl-modem-daemon status; sudo grep model /etc/modprobe.d/* ; sudo dmidecode|grep roduct; lsmod | grep snd 

Please post the full Terminal output into the same, original question that you previously created at answers.launchpad.net

Step 5

Reboot and retest sound using the headphones and the speakers. Check if you are running a Gnome session in "Gnome Failsafe" mode. Speakers will be disabled in "Gnome Failsafe" mode! After rebooting, please verify that you have posted the full Terminal output from step 3 and step 4 into the same, original question that you previously created at answers.launchpad.net

Step 6

Run the following command in a Terminal:

pavucontrol

In this application - PulseAudio Volume Control - switch to the "Playback" tab and increase System sounds volume to 100%

Step 7

Run the following command in a Terminal:

gnome-alsamixer

In this application, make sure to set all channels to high volume levels. Make sure the different speakers (especially 'Front', 'Master', and 'PCM") are NOT muted and NOT set to low volume levels in gnome-alsamixer. On some Toshiba laptop models (T40, T43p, ... R51e ...), the audio is muted, if either Headphone or Line Jack are NOT muted in alsamixer. See also ALSA Wiki FAQ [1]. Also, if Headphone Sense or Line Jack Sense are unmuted, audio is dead (R52, X40). By default the Sense settings are not shown in GNOME. A channel is muted in alsamixer, if there is an "MM" under that specific channel/volume bar. On some Toshiba laptop models, setting the PCM channel volume higher than 70% in alsamixer, may result in clipping (for example: very "harsh" and distorted sound both on the internal speakers and on headphones plug), regardless of the Master channel. Problem with audio clipping HP Laptops in the dv5, dv6, dv7 series and some HP Mini netbook computers have a strange problem in Ubuntu. When you plug in the headphones, you will hear sound via the headphones and speakers at the same time. The following link should provide a workaround for that issue: Problem with headphones

Step 8

Please also report if you cannot hear sound through the speakers, the headphones or cannot hear sound on both.

Step 9

If you are using a dual boot system (even with Windows and Ubuntu installed on separate partitions), then make sure to set the sound volume in Windows to a high level before booting into Ubuntu. Also make sure to use the special function keys in Windows to make sure the loudspeakers are physically switched ON and working properly in Windows before installing and testing Ubuntu. This step is necessary with certain Toshiba Tecra laptops.

Step 10

In System/Administration/Users and Groups, make sure that your normal user and the root user are members of the following 5 groups: pulse pulse-access pulse-rt audio video

Step 11

Run the command gnome-volume-control and set the Sound Theme to "No sounds". The Sound Theme tool is also accessible via System > Preferences > Sound

Step 12

Try connecting headphones to different audio jacks/ports on the back-panel of the sound-card until you hopefully hear sound

Step 13

If you happen to have two sound-cards installed in your pc, one integrated into the motherboard - for example: an hda-intel audiochip - and one inserted into a PCI slot, then try removing the PCI audio card, reboot your pc and retest sound using only the motherboard's on-board audio chip. If you absolutely need to get the PCI audio card working, try disabling the motherboard's on-board audio chip via the BIOS. Then retest sound in Ubuntu.

Step 14

Please also specify the exact model and make of your PC (if possible) in the new thread that you created at Launchpad Answers Forum.


Other Pages

For some initial suggestions please also read the following pages

!!! Check for correct /etc/modprobe.d/alsa-base.conf options on the following pages:


Other Useful Information for the Launchpad Answers Team

The following string needs to be added to the /etc/modprobe.d/alsa-base.conf file options snd-hda-intel model=YOUR_MODEL Valid model names (that replace YOUR_MODEL) depending on the codec chip, can be found here and here. You can find your codec chip name using this command

cat /proc/asound/card*/codec* | grep Codec

Each combination of audio codec, audio mixer and audio device name requires a very specific configuration in the alsa-base.conf file, if the audio chipset does not work out-of-the-box. To see if there is more than one alsactl executable in your path and remove the wrong/oldest one please copy&paste the following command into a Terminal and press the <enter> key:

sudo which alsactl

Having more than one alsactl can cause your sound settings to be muted during every boot of the Ubuntu system. In order to understand the various hda_intel related errors that might be mentioned at the end of the ALSA Information script output that was uploaded to the Pastebin website, please read the following documentation: HD-Audio documentation


How to install an alternative audio system called OSS4 (instead of ALSA)

If you want to use OSS4 instead of ALSA, please follow all the steps here: | OSS4 guide