when i insert an audio cd or a dvd i can not hear any sound. I have installed ubuntu on my imac. How can i solve this?

First place to look is double click the sound icon in your top panel and make sure the sound did not get muted during the installation and the correct volume controls are up high enough (you can see more volume controls there if you click Edit/Preferences
Second place to look is System/Preferences/Sound

Having done that, and if the problem persists, you will be able to give more information here.

Done all but the problem still persists

As I have said, i tried looking at the volume control, system preferences/sound but still no sound.

Hi, as there is apparently no sound at all from your computer, and you haven't mentioned if your setup is mono, stereo, or surround sound, other than re checking that any external power to speakers is connected, I suggest there may be a more basic problem revealed n these Ubuntu instructions

https://help.ubuntu.com/community/SoundTroubleshooting#Configuring%20default%20soundcards%20/%20stopping%20soundcards%20from%20switching

https://help.ubuntu.com/8.04/musicvideophotos/C/index.html

If you don't find your answer there, and know the name and type of your sound card, that may help here also.

Hope that helps you

Hi,

I had exactly this problem, using an iMac. I solved it by plugging in external speakers - I never got the built in speakers to work.

At first this only worked if turning up the external speakers VERY high. But to solve this, just open a terminal, type "alsamixer" and hit enter. Use the right arrows until you get to the IEC958 item, and press "m" to unmute the sound channel. Then logout, and back in again, your sound should work (found this on http://ubuntuforums.org/showthread.php?t=230125).