[pulseaudio-discuss] PulseAudio, switch audio output on device connection

[Mark Gaiser]

On Mon, Oct 6, 2014 at 12:57 PM, Mark Gaiser <markg85 at gmail.com> wrote:
> On Mon, Oct 6, 2014 at 12:49 PM, Tanu Kaskinen
> <tanu.kaskinen at linux.intel.com> wrote:
>> On Mon, 2014-10-06 at 12:39 +0200, Mark Gaiser wrote:
>>> On Mon, Oct 6, 2014 at 12:35 PM, Tanu Kaskinen
>>> <tanu.kaskinen at linux.intel.com> wrote:
>>> > On Thu, 2014-10-02 at 13:41 +0200, Mark Gaiser wrote:
>>> >> On Thu, Oct 2, 2014 at 11:04 AM, Tanu Kaskinen
>>> >> <tanu.kaskinen at linux.intel.com> wrote:
>>> >> > On Sun, 2014-09-28 at 21:16 +0200, Mark Gaiser wrote:
>>> >> >> Hi PulseAudio list,
>>> >> >>
>>> >> >> Note: please keep me in CC, i'm not registered on this list.
>>> >> >>
>>> >> >> I've been having this issue for as long as i use Linux (with
>>> >> >> pulseaudio) but never really bothered to look into the issue and try
>>> >> >> to resolve it. That's something i've been trying to tackle for a few
>>> >> >> days now without any notable success.
>>> >> >>
>>> >> >> First to clear make my use case clear.
>>> >> >> - I have a USB headset (but the same is true for jack).
>>> >> >> - On windows and mac, whenever i plug in a headset (usb or jack) all
>>> >> >> audio is redirected to that device.
>>> >> >>
>>> >> >> My linux setup:
>>> >> >> - Archlinux x64 (fully up to date)
>>> >> >> - KDE 4.xx
>>> >> >>
>>> >> >> What i want to accomplish is to have the same hassle free use case on
>>> >> >> linux as it works on windows and mac. My (fairly default) default.pa
>>> >> >> can be found here [1]. The only things i added (as far as i can
>>> >> >> remember) is:
>>> >> >> # automatically switch to newly-connected devices
>>> >> >> load-module module-switch-on-connect
>>> >> >>
>>> >> >> Which i did because it "looked" like the thing i needed based on one
>>> >> >> of the comments in [2]. It doesn't seem to do anything for me though.
>>> >> >>
>>> >> >> So how do i let PulseAudio redirect all audio output to (the last)
>>> >> >> audio device that i connected to it? Just like it works on Windows and
>>> >> >> Mac? I mean, i can change output sinks in pavucontrol, but that is
>>> >> >> hardly a sane way to do every time. There must be "some" easy way out
>>> >> >> there to do this, right?
>>> >> >>
>>> >> >> Also, it would be very nice of the audio switched sink while audio is playing.
>>> >> >>
>>> >> >> I prefer doing this using just default pulseaudio and linux commands.
>>> >> >> I know of the "paswitch" git project somewhere that allows me to
>>> >> >> switch output devices, but i don't believe that's the right way to do
>>> >> >> something like this.
>>> >> >>
>>> >> >> I hope this list could share the appropriate way in getting this done.
>>> >> >>
>>> >> >> For reference, i tried the same use case in Ubuntu, Kubuntu and Magaia
>>> >> >> (plug in a headset, play music and listen where the sound comes from).
>>> >> >> In all cases no sound was coming out of my headset. All sound came out
>>> >> >> of the speakers (that are connected via a jack plug).
>>> >> >
>>> >> > I don't know why it's not working for you, but here's some information
>>> >> > that may help with figuring it out.
>>> >> >
>>> >> > The first thing to note is that USB headsets and headphones that are
>>> >> > plugged into an audio jack are handled differently.
>>> >> >
>>> >> > The policy of moving streams to a newly plugged-in USB headset is
>>> >> > handled by module-switch-on-connect. That module changes the default
>>> >> > sink to a newly plugged-in sound card, and moves streams if and only if
>>> >> > the following conditions are fulfilled: the stream is currently playing
>>> >> > to the sink that was the old default sink, and you have not previously
>>> >> > explicitly moved the stream.
>>> >> >
>>> >> > The policy of switching to the headphones when you plug them to an audio
>>> >> > jack is handled by module-switch-on-port-available. That module never
>>> >> > moves streams. Instead, it just switches the port on the sink that has
>>> >> > the headphone port. I don't know the details of your setup, but if the
>>> >> > jack to which you have connected the speakers is part of a different
>>> >> > sink than the one that handles the headphone jack, then audio won't
>>> >> > automatically move to the headphones.
>>> >> >
>>> >> > The above is a description how things are, not necessarily of they
>>> >> > should be.
>>> >> >
>>> >> > --
>>> >> > Tanu
>>> >> >
>>> >>
>>> >> Hi Tanu,
>>> >>
>>> >> Thank you very much for your reply. For the moment, lets focus on the
>>> >> case where a USB headset is plugged in.
>>> >> In my current case (with live cd's/dvd's and a natively installed
>>> >> archlinux) where the case is: (for clarity):
>>> >> - Play some music using some pulseaudio enabled player
>>> >> - Sound comes out of the speakers (jack connection)
>>> >> - Plug in a USB headset
>>> >> - Sound is still being send to the connected speakers (jack) and not
>>> >> the newly attached headphone (usb)
>>> >>
>>> >> This is repeatable for me on a multitude of distributions, even with
>>> >> completely different hardware (same usb headset every time).
>>> >>
>>> >> Therefore i doubt a fault in my configurations since i would expect
>>> >> distributions like magaia, ubuntu and kubuntu to have this sorted out
>>> >> of the box. Anyway, for reference, my settings again:
>>> >> http://pastebin.com/NL7hbvS6
>>> >>
>>> >> Is there any test i can run to debug this issue and figure out where
>>> >> things go wrong?
>>> >
>>> > I don't think there's any simple test. You could add logging to the
>>> > sink_put_hook_callback() function in module-switch-on-connect.c for
>>> > every case where the function decides to return without moving streams,
>>> > and then see from the log why the moving is not happening.
>>>
>>> Just wondering, can you reproduce this issue?
>>
>> I tried now, and no, I couldn't reproduce. I installed PulseAudio from
>> current git master, started to play music with Rhythmbox, ran "pactl
>> load-module module-switch-on-connect", and plugged in a USB headset. The
>> music moved to the headset automatically.
>
> I will try those exact steps as well and report back with my findings
> (as soon as i get home).

Ok, i tried a bunch of different players. The results:
- mplayer (smplayer as well) : sound doesn't switch when attaching a headphone
- rhythmbox : refused to play any plain simple mp3 file
- amarok : sound doesn't switch when attaching a headphone
- dragon player : sound doesn't switch when attaching a headphone
...

I did get rhythmbox to beep once and that one came out of my headset.
Based on that i'm beginning to think that there is some GTK vs Qt
difference in play here.

One thing i did found (in the kde settings) was that i can prefer my
headphone to be first in sound order. Funny thing is, this is actually
working for an application like amarok which then behaves as i expect.
However, other apps don't seem that happy to comply and just spew out
audio to my jack port.

Could you perhaps test if you can get the same thing working under mplayer?
mplayer -ao pulse <some_mp3_file>

That is a quite simple test - easy to reproduce - and doesn't give me
the expected result. I wonder how that works with you.