After fresh installing 13.04 at my HP ProBook I can have sound only in one application at a time.
When I use Skype, there's no sound in Clementine, SMPlayer, etc.

I tried to reinstall ALSA and PulseAudio like this:

sudo apt-get remove --purge alsa-base pulseaudio

sudo apt-get install alsa-base pulseaudio

sudo alsa force-reload

But with no effect.

In Skype, I have only ALSA (hw:....), there's no 'PulseAudio' option.