pulse: Fix assertion if pulseaudio is not running
pulse: Fix assertion if pulseaudio is not running

mratajsky/libmatemixer,dnk/libmatemixer,monsta/libmatemixer,monsta/libmatemixer,jrtc27/libmatemixer,mate-desktop/libmatemixer,mate-desktop/libmatemixer,mratajsky/libmatemixer,mratajsky/libmatemixer,jrtc27/libmatemixer,dnk/libmatemixer