If you are having trouble getting sound to work on a CS Linux machine, please follow these steps:

1. Speakers or Headphones - In order to hear audio output, you must either have headphones or external speakers. If you are using a system with a Dell LCD monitor, you may have a speaker bar mounted along the bottom of the monitor. Be sure the speakers are turned on and that the volume control on the speakers themselves is turned up. If you are using headphones, be sure they are plugged into the proper headphone audio jack. If you are using a Dell Optiplex computer, you can plug your headphones into the headphone jack on the front of the system. On some Dell systems the headphone jack is located under the gray cover on the front.

   If your computer doesn't have speakers and you would like to request a set, please let us know.

2. Audio Control with Gnome - If you are using Gnome, you should see a little speaker icon in the panel (in the upper right hand corner of the screen by default). Right click on the speaker icon and select "Open Volume Control" from the menu. On most of the Dell computers in the department, the volume is controlled by multiple sliders, including Master, PCM, and/or PCM-2. Other sound cards and other machines may behave differently, so your best bet is to experiment. But, on the Dells we recommend that you set the Master, PCM, and CD sliders at full volume and set the remaining sliders in the middle. Also make sure none of the mute buttons are checked.

   Also be sure you have the correct audio device set. From the volume control application, select "Change Device" from the File menu and be sure the "Alsa" device is selected and not OSS.

   Once you have these sliders positioned, exit the volume control window and again right click on the speaker icon in the panel. This time select "Preferences" from the menu. This allows you to select the audio channel you want the Gnome volume slider to control. The selection here is dependent on the hardware but on most CS Dells you will want to select either Master or PCM.

   Also note that some systems have an internal speaker that is controlled independent of the external speakers. On most systems, the internal speaker is controlled by the Master Mono slider so you probably want to just mute that one to disable it.

   Once you have this all set up, you can then control the volume by just clicking the speaker icon in the Gnome panel and using the slider that should pop up.

3. Audio Control with KDE - If you are using KDE, the same issues related to using Master, PCM, and Master Mono controls is at play so you should first read the above section for setting things up when using Gnome. In KDE, you can open the volume control window by selecting Alsa Volume Control from the KDE Sound & Video application menu. From this application, you will have to experiment with what channels control the volume on your sound card but on most CS Dells the volume is controlled by the Master and PCM channels.

   In KDE you can add a volume control to the KDE panel in a couple different ways. One way is to right click in the panel and then select:

   Add->Applet->Sound Mixer

   This adds a little volume control applet to your panel. Once you have added this, you will likely want to configure it to only display the channels you care to control. To do this, right-click on it and select Channels under Device Settings. Just uncheck the ones you don't care about.

4. Audio Control with other window managers - If you are using something other than Gnome or KDE, you are largely on your own. However, you can probably just run gnome-volume-control from the command prompt to bring up a volume control window. See the section above on Gnome for details about what channels control the volume.

5. Testing - While you are experimenting with various volume settings, you will need a way to generate a test sound. One easy way to do this is using the audioping command that is installed on the local CS systems. This command just pings some host and generates a sound on each packet it receives. You can envoke this by just running "audioping localhost" and you should hear a "drip" sound each second. When you want to stop this, just hit Control-C.

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