I have this problem with playing back animations in blender. I use linux, with KDE3 as my windowmanager.
Whenever I press “play” nothing happens. I suspect the window hides behind the blender main window, since I always have to retrieve a rendered stillframe with alt-tab. When I do not use KDE3 it all works fine, but not starting a windowmanager is not really practical.
Does anyone know how to fix this?