Kubuntu Sound notes -incomplete...

Amarok Help provided:

Phonon is the multimedia framework used by Amarok. It was created to allow KDE 4 to be independent of any single multimedia framework such as GStreamer or Xine and to provide a stable API for KDE 4's lifetime. As an added bonus, it simplifies development by providing a simple API that works across different platforms such as Windows and OS X.
The result of all this for you, the user, is that you can choose the multimedia framework that works best for you. This is usually pre-configured by your distribution.
Playback problems in Amarok are typically not Amarok issues, but rather Phonon issues, as Amarok doesn't handle sound directly anymore.

Depending on your OS and distribution, you may need to use ALSA, OSS, PulseAudio, or something else as your default playback device. Find one that works for you with the Test button and apply to all types of output. If you would like different types of output to go with different devices, this is possible as well.


Depending on your operating system you may see options such as Xine, Gstreamer, VLC, or DS9 (Windows) here. The recommended phonon-backend for Linux® users is VLC or Gstreamer.
If you don't see VLC or Gstreamer, install the package for it. For most distributions the package for VLC, for example, would be phonon-backend-vlc.
Each backend comes with its own codecs, so depending on the backend you choose you will need to also download the codecs, as most distributions don't ship them for legal reasons.
For information on codecs and playing mp3s see the mp3 information page.

My current backend is Photon GStreamer 4.6.2. Since it works well, I won't install another backend.