Interfere in pulseaudio volume between mpv and libmpv

[bylee20]

PulseAudio supports per-application volume and it kept by PulseAudio.

When I changed volume in mpv, the changed volume also applied in libmpv client.
I've tried to set audio-client-name but it only changes the string in volume control and didn't solve the problem.

Is there any solution for this?

[ghost]

The audio-client-name option should handle this. Not sure why it wouldn't work?

[bylee20]

No idea. When launched client only, the volume control displays the name what I set to audio-client-name but if mpv is running, libmpv client does not even appear in volume control. Defintely they share same control.

[ghost]

I think this happens when the audio-device-list property is queried. It creates a connection without the proper client name set. It should disconnect immediately, though, and I see no reason why it would override the stream name. (Or maybe this is a different bug.)

[bylee20]

Partially fixed. Now I can see both controls in mixer window and I can control them independently when they're running at the same time.

However, for instacne, If I execute client after excuted mpv --mute <video>, then the initial volume of client is muted.

Now I doubt pulseaudio because they're synced even if I can see separated controls.

[ghost]

Looks like PulseAudio loves to force application devs to add shitty singletons.

[ghost]

Or maybe I'm misunderstanding... needs more investigation.

[ghost]

(Yeah, I was misunderstanding.)

I tested it, I can't see that they conflict in any way. What might cause confusion is that the stream title contains "mpv" by default. You can override it by setting the title option.

[bylee20]

You can't reproduce this?

Setting title doesn't work. In fact, I've set title to ""(empty string) always.

[ghost]

You can't reproduce this?

No.

Setting title doesn't work. In fact, I've set title to ""(empty string) always.

Then maybe dump and check the values ao_pulse.c passes to the pulseaudio APIs.

[bylee20]

Finally I found the source. It's the line set PA_PROP_MEDIA_ROLE:

(void)pa_proplist_sets(proplist, PA_PROP_MEDIA_ROLE, "video");

If I comment out that line, no more interference exists.

I don't know the exact purpose of each role because the document says nothing, it seems that the PA_PROP_MEDIA_ROLE is designed for making it possible to interfere between streams using PulseAudio at the very first time.
For instance, if a 'phone' role stream is started from any application, all other streams are muted including external applications.

I found that VLC also sets "video" role and I can see that VLC and mpv also interferes each other.

With some test, "video" and "music" also interferes but "game" does not interfere.
Also, no specific role(which is set "none" by internal PulseAudio) does not cause interference.

[ghost]

The "video" role caused some trouble with other things too.

But it's entirely a pulseaudio issue.