I have the following problem: I have brand new Fedora 10 installed and everything works file except one thing - I cannot mute my speakers when I plug my headphones. It is not just that Linux does not automatically detect that my Headphones are plugged in and mute the speakers - but cannot even manually disable the speakers and let only the headphones make sound. Everything I try in the Mixer - it seem that Headphones and Speakers are on the same channel. Do you have any idea how i can switch between the two?

Seems like the drivers aren't working as they should. Try get your sound card details and see what other Fedora 10 users have done. There should be forums around similar issues as long as your sound card is not too obscure.

My notebook is MSI EX700 and the sound card is Realtek. All the drivers available on the Net( including the official MSI web site ) are for Windows XP/Vista so it seems the problem is not in the drivers ( my sound is ok ). Could the problem be in driver configuration???

of course the drivers are going to be for windows (most linux distros are the effort of the open-source community). you are probably going to have to go edit configuration files, so if you check on the fedora forums, i am sure others are in the same situation as you.