Sound Problems

KDE 4 uses the wrong sound device.

That is not an error, but a configuration issue. To tell KDE 4 which soundcard to use (or prefer if available), open System Settings and go to Multimedia in the General tab.

Devices from /etc/asound.conf or ~/.asoundrc are not listed.

Phonon uses a function introduced in ALSA 1.0.14 to find those devices. To make this function list your entry you need to add a name hint. E.g.

hint {
    show on
    description "Name to display for the device"
}

A complete example that adds a new volume control named Phonon to your mixer:

pcm.softvolPhonon {
    type softvol
    slave.pcm "default:CARD=0"
    control {
        name "Phonon"
        card 0
    }
    min_dB -51.0
    max_dB 0.0
    resolution 100
    hint {
        show on
        description "My Soundcard with extra Volume Control"
    }
}

You are using KDE 3 and you keep losing sound. Sometimes it works, sometimes it doesn't.

KDE 3.x uses the aRts sound system. In earlier versions there were a number of problems, but in recent years the only problem remaining seems to be that aRts hangs on to the sound system when it has finished with it. To cure this, use kcontrol > Sound & Multimedia. Towards the bottom of the General tab there is a setting for 'Auto-suspend if idle after:' Set this to 1 second.

You have multimedia keys but KDE doesn't recognise them

This link has a clear description of what one user did to make his Volume-up and Volume-down keys work.