I just installed Xubuntu for the first time and getting audio to work was non-trivial so figured I'd post some tips. My situation is I have a 5.1 + mic sound card (Sound Blaster). Getting things to work in Ubuntu & Kubuntu was straightforward; but Xubuntu is harder (I'm with Torvalds [Link], though, that Xfce is the way to go).
  1. Make sure pavumeter is installed. It's the PulseAudio Volume Control.
  2. Use it to configure your sound-card to the right option. For me it's
    Analogue Surround 5.1 Output + Analogue Stereo Input
    which is a bit strange given the mic is mono. A simple stereo sound card is stereo duplex. pavumeter will be under Multimedia in the Applications Menu (top left).
  3. You need to make sure everything is configured correctly under the Alsa Mixer (also under Multimedia). You need to pick the relevant controls using the "Select Controls..." dialogue box.
  4. Make sure you check the boxes for "Analogue Source" and "Shared Mic/Line in". These have to be set to mic or else the mic won't work (this took me a while to work out). Microphones require a DC bias, so the distinction is important.
  5. Check the input and output is working correctly in pavumeter.
  6. You can set gmusicbrowser (which I actually quite like, despite no WMA support) to play/pause when you hit the Pause key on your keyboard by going
    Settings>>Settings Manager>>Keyboard>>Application Shortcuts>>Add
    Then the command is
    gmusicbrowser -cmd PlayPause
    And then hit OK and hit Pause/Break on the top-right of the keyboard. You can also set the thunar command to go with window key + e for "Explorer" type behaviour.

Now to get my Hantek oscilloscope working...