ANNOUNCE: xfce4-mixer 4.9.0 released

[Guido Berhoerster]

* Sergio <sergiocmailbox-xfce at yahoo.com.br> [2012-10-26 19:08]:
> > > May I ask that this option be added to the 'Properties'
> > dialogue?
> > > Updated today to xfce4-mixer 4.10 and no one would ever
> > know what to do to change the default mixer app for the
> > panel plugin.
> > > There isn't an xfconf channel property for that. You
> > could answer me how to add one here but a new user would
> > have no way to know.
> > > 
> > > Then, just for completeness' sake, if I add something
> > else other than xfce4-mixer (like pavucontrol) then the
> > right-click context menu would show 'Run PulseAudio Volume
> > Control' instead of 'Run Audio Mixer', right?
> > > I mean that entry should read the desktop file for the
> > defined mixer and not be hard-coded (not saying it is as I
> > haven't obviously changed the default mixer to open yet).
> > 
> > Well, the problem with that is that you can't reliably
> > determine
> > a desktop file corresponding to an arbitrary executable
> > entered
> > into the configuration dialog.
> 
> True, would have to think about that.
> 
> > Apart from that issue, what
> > is
> > the use-case for that, why would one use the xfce4-mixer
> > applet but not xfce4-mixer and for what kind of target
> > audience
> > is that relevant?
> 
> I would say most people.
> Not because of having or not pulseaudio. It's just that xfce4-mixer is a GTK interface for alsamixer and pavucontrol does other things (like settings for each app that's using it).
> So the user should, IMO, be able to bind the mixer applet to open whichever sound related app he wants.
> One can open any app from the menu of-course but it's more intuitive to use the mixer for the preferred one.
> 
> > So far seems to be an issue with systems that have
> > pulseaudio
> > installed and prefer pavucontrol over xfce4-mixer because
> > the
> > pulseaudio integration in gstreamer is poor.
> 
> As I said they do different things (and some in common). One isn't a replacement for the other.
> We can have either alsamixer or pavucontrol or both.

Pulseaudio provides a different abstraction over Alsa/OSS and
that is a full replacement for the abstraction offered by the
GStreamer mixer interface. While GStreamer has a PA plugin, it
isn't very useful since it only exposes one master volume track
for all device (and at least on my system not even that works).
Also in its default configuration PA interferes with the low
level controls exposed by the GStreamer Alsa plugin, see
http://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/PulseAudioStoleMyVolumes
So no, it does not make much sense to use both side by side.
Since everyone seems to use PA directly for mixers instead of the
GStreamer PA plugin, it doesn't look like the situation will
improve there. The most viable solution would be for someone to
write a new xfce4-mixer-pa variant from scratch around PA.

> > But in that
> > case I
> > think that distributions shipping pulseaudio by default
> > should
> > redefine XFCE_MIXER_PLUGIN_DEFAULT_COMMAND to pavucontrol
> > in
> > order to provide a decent user experience out of the box
> > rather
> > than forcing every user to change it in the plugin
> > configuration
> > dialog.
> 
> As explained this is a misunderstanding.
> 
> > And I'd argue that if a user is technical-savvy
> > enough to
> > know what pavucontrol is and why he wants it, he probably is
> > also
> > capable of entering it into xfce4-settings-editor.
> 
> No, pavucontrol is a basic GUI app, not technical at all.

_Using_ pavucontrol is not, however knowing that "PulseAudio
Volume Control" corresponds to /usr/bin/pavucontrol and that it
needs to be entered into a configuration dialog of the
xfce4-mixer applet in order to make the "Audio Mixer" menu item
start a functional mixer when your system uses pulseaudio does
presuppose some techical understanding.

> And only now I guess that for me to do that I must *add*
> (because it isn't there by default) some
> XFCE_MIXER_PLUGIN_DEFAULT_COMMAND property to xfce4-mixer
> channel:
> 
> $ xfconf-query -l -c xfce4-mixer
> /sound-card
> /sound-cards/PlaybackInternalAudioAnalogStereoPulseAudioMixer
> /sound-cards/VIA8233AAlsamixer
> /window-height
> /window-width

No, that is the configuration of the mixer, the panel applet
configuration is stored in the xfce4-panel channel in a
sub-property below /plugins.
The XFCE_MIXER_PLUGIN_DEFAULT_COMMAND macro could be patched by
distros using PA by default if thy desire, if there is any demand
from distro maintainers I could make that easier, e.g. through a
compile-time option.

-- 
Guido Berhoerster