The question I have is.... Are you running another desktop and then
logging out and then logging into KDE? Or, are you logging out of KDE and then quickly
logging back in? I ask that since a while back, more than a year now, If I logged out and
quickly logged back in I would have no audio. If I recall, the pulseaudio daemon stayed
alive even after logout and the new session couldn't get a new one. I'm sure they
are not related to your issue except that maybe there is a "race condition"
involved.
I am always using KDE although I have gnome installed and I have also
6 virtual desktop but I display the same desktop in all of them. I am
not logging out and quickly in again...
Thanks,
Frédéric