Bug#541538: pulseaudio: disable flat volumes

[Thomas van der Berg]

I've recently installed Debian Testing and have been disturbed by
flat-volumes being on by default. It's completely unintuitive when
raising my VLC volume suddenly raises the volume of other programs on my
OS! The whole reason I'm raising a program's volume is because I want it
to be louder than the rest. The "flat-volumes = yes" default just causes
mysterious audio behaviour that I've never experienced on Ubuntu,
Windows or OSX. In fact I thought my VLC was bugged until I went to
investigate the issue.

In fact, both Ubuntu and Arch[1] already explicitly disable the
"flat-volumes" setting because it causes unintuitive and problematic
behaviour. Here's just a few of the many reports people made about
problems with flat-volumes I've found: [2][3][4]. And you can find many
more just by searching "PulseAudio flat volumes" on any internet search
engine.

"flat volumes" supporters justify their decision with a Microsoft
research paper from 2004 [5], however, it seems that even Windows 7 was
no longer following the idea presented in this paper [6], and one can
say that PulseAudio's implementation(allowing each application to set
the master volume higher) doesn't even match the paper's idea(allowing
each application to set its own relative volume, and having the system
adjust each application's volume levels in the background to match the
master volume).

Supporters also claim that the flat volumes system is more intuitive or
easier for non-experts to understand, but I think just the large
volume(no pun intended) of reported issues with this easily disproves
that idea.

I hope Debian follows suit and finally turns the setting explicitly off
by default like Ubuntu and Arch have already (very sanely) done.

[1] https://wiki.archlinux.org/index.php/PulseAudio#daemon.conf

[2]
https://www.reddit.com/r/linux/comments/2rjiaa/horrible_decisions_flat_volumes_in_pulseaudio_a/
[3] https://bugzilla.redhat.com/show_bug.cgi?id=1265267
[4] https://features.opensuse.org/310668

[5]
http://www.patrickbaudisch.com/publications/2004-Baudisch-CHI04-FlatVolumeControl.pdf
[6] http://permalink.gmane.org/gmane.comp.audio.pulseaudio.general/17426