Ufter upgrade Debian SID something wrong with sound - PulseAudio

[Csanyi Pal <csanyipal@gmail.com>]

Hi,

I upgraded my Debian SID yesterday and since then something is wrong
with my sound.

I have installed GNOME and Window Maker X Window environments, and my
favorite is WM.

I'm using IRSSI and after upgrade I can't heare anymore the beep sound
when someone send me a message.

Evolution doesn't beep when mails arrived.

I'm using Skype too and can't heare it's sounds.
Skype says:
It appears your system has PulseAudio running: to change sound settings
you need to use your Desktop Manager volume control or PulseAudio volume
control. 

When I try to make a test sound with Skype I can see on my WMMixer that
that the volume suddenly come to zero and afte ra while it come back to
the normal volume but during that I can't heare any sound.

I'm using Rhytmbox and I can heare music and voice from it.

So one application works and another doesn't work.

When I run Gnome-control-center I can't setup there any PulseAudio
thing.

How can I solve this problem?

-- 
Regards from Pal