Bug #295832 “Alsa does not honor pcm.!default because of /usr/sh...” : Bugs : pulseaudio package : Ubuntu

Revision history for this message

Martin Stjernholm (msub) wrote on 2008-11-29:

#1

Bug #198453 contains a long discussion about this, and although I haven't read it thoroughly, the gist is apparently that it's generally a good thing to do that override.

Still, people might have any number of reasons for wanting things their own way. I guess a problem here is that the alsa config files doesn't provide a way for letting local configuration properly override hook based configuration.

In the meantime, until that is fixed, I suggest an option in /etc/default/pulseaudio to disable the overrides of pcm.!default and ctl.!default. That way it's at least possible to cope in a system level without resorting to editing files outside /etc.

Revision history for this message

Lucas Gadani (lgadani) wrote on 2008-12-04:

#2

I understand that it might be a good idea to leave pulse as default on new Ubuntu installations, however it should be possible to override this setting with a file in /etc or user's home folder.

Currently, the only way to disable this option is editing a file in /usr/share .

Maybe pulseaudio could provide an option through debconf that sets it as the default alsa output, so we could disable without changing files inside /usr/share .

Revision history for this message

Daniel T Chen (crimsun) wrote on 2009-01-06:

#3

I can't reproduce this symptom in 9.04. Please try again.

Changed in pulseaudio:
status:	New → Incomplete

Revision history for this message

Lucas Gadani (lgadani) wrote on 2009-01-06:

#4

I don't have 9.04 here, but I can still reproduce this symptom in 8.10.

Revision history for this message

Lucas Gadani (lgadani) wrote on 2009-01-07:

#5

I've installed Ubuntu 9.04 alpha 2 and applied all the updates for this test. I don't have two sound cards in this test machine, so I can't confirm exactly the same behaviour, but I've made a simpler test as described below and I believe the problem is still present.

- start alsamixer
- check that default mixer is pulseaudio

- create a ~/.asoundrc file with the following content:

--- cut here ---
ctl.!default {
type hw
card 0
}
--- cut here ---

- start alsamixer
- check default mixer and it's still pulseaudio (bug!). ~/.asoundrc should override default settings, but it's not working.

- comment ctl.!default entry in /usr/share/alsa/pulse-alsa.conf

- start alsamixer
- check that hw:0 mixer is the default mixer.

- change ~/.asoundrc with the following content:

--- cut here ---
ctl.!default {
type pulse
}
--- cut here ---

- start alsamixer
- check that pulseaudio is the default mixer. just to make sure ~/.asoundrc is being read. (ok!)

So, the conclusion is that's not possible to change default alsa devices without changing files in /usr/share.

Revision history for this message

Daniel T Chen (crimsun) wrote on 2009-01-08:

#6

Please note that your ~/.asoundrc is incomplete. You are only overriding the control definition; you need also to override the pcm definition(s), e.g.,

pcm.!default {
type plug
slave hw:0,0
}

ctl.!default {
type hw
card 0
}

Revision history for this message

Lucas Gadani (lgadani) wrote on 2009-01-09:

#7

Yes I understand, however, even when overriding the pcm.!default I have exactly the same problem with Jaunty 9.04 or Intrepid 8.10.

How are you trying to reproduce this? What are the steps you're doing while trying to reproduce this bug?

I was able to reproduce this using a kvm image with 2 sound cards. Pulse is always the default regardless of the setting in ~/.asoundrc , unless I change /usr/share/alsa/pulse-alsa.conf . I could provide you disk images reproducing this bug and/or a video of how to do it.

The exact same .asoundrc used to work with Hardy 8.04 and Gentoo Linux, so I'm pretty sure this is a problem with Ubuntu's current pulse package.

Revision history for this message

Daniel T Chen (crimsun) wrote on 2009-01-11:

#8

I tested using the ~/.asoundrc pasted in my previous comment. I can also use a second (hw:1) usb audio device. PulseAudio, in its default configuration returns an error, as proper/expected.

Revision history for this message

Daniel T Chen (crimsun) wrote on 2009-01-15:

#9

I've just verified the following:

1) a default jaunty daily-live skips ~/.asoundrc if pulseaudio is running
2) a default jaunty daily-live honours ~/.asoundrc if pulseaudio is *not* running

As this behaviour is intentional (note the name of the hook!), I'm closing this bug.

Changed in alsa-plugins:
status:	Incomplete → Invalid

Revision history for this message

Martin Stjernholm (msub) wrote on 2009-01-16:

#10

Intentional or not, it's bad behavior: It's clearly a dist configuration that cannot be overridden either by user or by local system settings. As said earlier: People might have any number of reasons for not wanting this hardcoded override that the pulse package does.

The default pcm/ctl is configurable in alsa, it no longer is when pulseaudio is running. If this pcm/ctl override were the only or prime reason to run pulseaudio then it'd be ok, but that's not the case.

I therefore persist: It would be good if this was overridable at least on the system level, typically through a setting in /etc/default/pulseaudio.

Revision history for this message

Daniel T Chen (crimsun) wrote on 2009-01-16: Re: [Bug 295832] Re: Alsa does not honor pcm.!default in ~/.asoundrc because of /usr/share/alsa/pulse-alsa.conf

#11

I don't agree with your assertion of a "configuration that cannot be
overridden either by user or by local system settings". If you don't
want the pulse pcm+ctl, then don't allow the pulseaudio daemon
to run, e.g., kill it. I concur that there is a usability bug in not being
able to easily {en,dis}able the daemon, but it's a bit of a stretch to
assert that the pcm+ctl configuration can't be overridden.

Please note as well that, in a default Ubuntu configuration, the
daemon will be invoked during session startup and will grab hw:*.
In such a case, ~/.asoundrc will be unusable involving hw:* unless
the hardware supports multiopen. Therefore, it is very much the
intent of the pulseaudio package to provide a pcm+ctl
configuration that overrides any other setting when the daemon is
active. You *must* disable the daemon (as noted above) to stop
this action.

I'm unsure how you intend to make pulseaudio work out of the box
and to still effect ~/.asoundrc with highest priority. In the case
where ~/.asoundrc conflicts with pulseaudio's pcm+ctl
configuration, how do you wish ~/.asoundrc to remain effected,
e.g., how would you add such logic checks?

----- Original Message ----
From: Martin Stjernholm <email address hidden>
To: <email address hidden>
Sent: Friday, January 16, 2009 4:51:14 AM
Subject: [Bug 295832] Re: Alsa does not honor pcm.!default in ~/.asoundrc because of /usr/share/alsa/pulse-alsa.conf

Intentional or not, it's bad behavior: It's clearly a dist configuration
that cannot be overridden either by user or by local system settings. As
said earlier: People might have any number of reasons for not wanting
this hardcoded override that the pulse package does.

The default pcm/ctl is configurable in alsa, it no longer is when
pulseaudio is running. If this pcm/ctl override were the only or prime
reason to run pulseaudio then it'd be ok, but that's not the case.

I therefore persist: It would be good if this was overridable at least
on the system level, typically through a setting in
/etc/default/pulseaudio.

I don't agree with your assertion of a "configuration that cannot be
overridden either by user or by local system settings". If you don't
want the pulse pcm+ctl, then don't allow the pulseaudio daemon
to run, e.g., kill it. I concur that there is a usability bug in not being
able to easily {en,dis}able the daemon, but it's a bit of a stretch to
assert that the pcm+ctl configuration can't be overridden.

Please note as well that, in a default Ubuntu configuration, the
daemon will be invoked during session startup and will grab hw:*.
In such a case, ~/.asoundrc will be unusable involving hw:* unless
the hardware supports multiopen. Therefore, it is very much the
intent of the pulseaudio package to provide a pcm+ctl
configuration that overrides any other setting when the daemon is
active. You *must* disable the daemon (as noted above) to stop
this action.

I'm unsure how you intend to make pulseaudio work out of the box
and to still effect ~/.asoundrc with highest priority. In the case
where ~/.asoundrc conflicts with pulseaudio's pcm+ctl
configuration, how do you wish ~/.asoundrc to remain effected,
e.g., how would you add such logic checks?

----- Original Message ----
From: Martin Stjernholm <msub@stjernholm.org>
To: crimsunkg@yahoo.com
Sent: Friday, January 16, 2009 4:51:14 AM
Subject: [Bug 295832] Re: Alsa does not honor pcm.!default in ~/.asoundrc because of /usr/share/alsa/pulse-alsa.conf

Intentional or not, it's bad behavior: It's clearly a dist configuration
that cannot be overridden either by user or by local system settings. As
said earlier: People might have any number of reasons for not wanting
this hardcoded override that the pulse package does.

The default pcm/ctl is configurable in alsa, it no longer is when
pulseaudio is running. If this pcm/ctl override were the only or prime
reason to run pulseaudio then it'd be ok, but that's not the case.

I therefore persist: It would be good if this was overridable at least
on the system level, typically through a setting in
/etc/default/pulseaudio.

Revision history for this message

Lucas Gadani (lgadani) wrote on 2009-01-16: Re: Alsa does not honor pcm.!default in ~/.asoundrc because of /usr/share/alsa/pulse-alsa.conf

#12

I also think it's bad behaviour. I have a sound card that supports multiopen, so I wanted to have both pulseaudio running and not have pulseaudio grabbing pcm.!default (because of some incompatibilities). Unfortunately, this is not possible without changing /usr/share/alsa/pulse-alsa.conf.

Maybe pulseaudio could have it's alsa configuration in /etc/asound.conf (so the root could override the configuration) or in /etc/skel/.asoundrc (so that every new user will have pulseaudio enabled by default, but overridable in it's configurations).

Revision history for this message

Martin Stjernholm (msub) wrote on 2009-01-18: Re: [Bug 295832] Re: Alsa does not honor pcm.!default in ~/.asoundrc because of /usr/share/alsa/pulse-alsa.conf

#13

Daniel T Chen <email address hidden> wrote:

> I don't agree with your assertion of a "configuration that cannot be
> overridden either by user or by local system settings". If you don't
> want the pulse pcm+ctl, then don't allow the pulseaudio daemon
> to run, e.g., kill it. /.../

That's sort of a "devil's choice" since pulseaudio is (or is becoming)
an integrated part of Gnome that other parts assume is running, thus
killing it makes various other things misbehave. In my particular case
I found it necessary to handle e.g. the system beep.

> Please note as well that, in a default Ubuntu configuration, the
> daemon will be invoked during session startup and will grab hw:*.

That's true in a default configuration, but it can be changed by local
settings. I have an /etc/asound.conf that adds dmix/plug devices on
top of the hw device, and I have corresponding local settings in
/etc/pulse/default.pa that makes it use those devices. This way I can
use pulseaudio for clients requiring it, together with clients that
use alsa directly (without passing through pulseaudio). Both work at
the same time, and I don't have hardware with multiopen support - alsa
does the mixing instead of pulseaudio.

This together with the change I'm currently forced to do in
/usr/share/alsa/pulse-alsa.conf is a quite well functioning setup.

My specific reason for not routing everything through pulseaudio is
that it still doesn't work well enough - I get choppy sound and
sometimes big latencies in some apps. This is hopefully a passing
problem, but nevertheless a big one for me right now. And my current
reason aside, there can always be many other reasons for not wanting
to route alsa traffic through pulseaudio and back again.

> I'm unsure how you intend to make pulseaudio work out of the box
> and to still effect ~/.asoundrc with highest priority. In the case
> where ~/.asoundrc conflicts with pulseaudio's pcm+ctl
> configuration, how do you wish ~/.asoundrc to remain effected,
> e.g., how would you add such logic checks?

I don't have any solution for that, I'm only pointing out the problem.
I guess it'd require some sort of priority system that controls hooks
too, which sounds like a fairly complex addition to alsa.

Because it appears to be nontrivial to solve "the right way", I
suggested instead only a sort of opt-out setting in
/etc/defaults/pulseaudio, so that it can be avoided at least on the
system level. Another alternative could perhaps be to place
/usr/share/alsa/pulse-alsa.conf (or a fragment of it) inside the /etc
tree.

And as for working out of the box, I can point out that the setup I've
outlined above works well straight away for most applications, in the
very common special case that they run locally and only need to access
the local sound hardware.

Daniel T Chen <crimsunkg@yahoo.com> wrote: