Comment 6 for bug 315971

Yes, as described in the original post, none of the volume controls (on the Volume control applet) adjusted the PCM channel.

I've worked around it with the manual setting of the mixer in alsamixer, but am curious to know what mechnism should set sensible mixer defaults on a released distro.

(I guess either Pulseaudio needs to ensure the mixer channels required by pulseaudio are brought up, or that the volume control applet exposes the required mixer settings.