Bug 55438

Summary:	channels aren't separated after switching between speakers and headphone (sometimes)
Product:	PulseAudio	Reporter:	alex <devkral>
Component:	core	Assignee:	pulseaudio-bugs
Status:	RESOLVED MOVED	QA Contact:	pulseaudio-bugs
Severity:	normal
Priority:	medium	CC:	kamil.lech.roman, lennart
Version:	unspecified
Hardware:	x86-64 (AMD64)
OS:	Linux (All)
Whiteboard:
i915 platform:		i915 features:

Description alex 2012-09-28 23:20:21 UTC

Symptoms:
-music sounds strange
-playing front-left (gnome) is also heard on the right headphone speaker and the other way around

Reproduction (speakers are connected, also the headphone):
1. plug out headphones, the sound should be hearable from the speakers
2. listen to music some time
3. plug in headphones
Now this problem appears sometimes (with the headphone, the speakers still operate fine). The problem can't be solved by restarting pulseaudio.
The weirdest thing is that the problem disappears after a while.
Sorry that I don't have more information. I hope you can reproduce the problem.

my conclusion:
It seems as if the left and the right channel are mixed to a distorted mono sound.
But this seems only to happen in headphones. Most probably it is a fault in the headphone detection (the headphone itself is new and works fine) or a hardware problem (broken driver?)

Technical data:
pulseaudio: git, build date: 22.9.2012
distro: archlinux
mainboard: GA-MA785GT-UD3H

Related bugs (seems so):
https://bugs.freedesktop.org/show_bug.cgi?id=53206

Comment 1 alex 2012-10-08 09:16:51 UTC

I think I found a fix.After using the command the sound gets normal (tests needed to be sure; it could be a coincindence):
pulseaudio --cleanup-shm

Comment 2 alex 2012-10-09 12:26:42 UTC

test failed. Again there is the problem with the channel map and using the command didn't help.

Additional information: What I used: pulseaudio git commit f0432ce6aedca5956f6086824120bb03559e6534 on archlinux

Ah another strange thing:
the normal speakers work flawless, just the headphones have this problem.
Also the jack detection doesn't work anymore

Comment 3 Raymond 2014-12-04 05:10:58 UTC

 /usr/share/sounds/alsa/Front_Left.wav is a mono wav file, this is normal  if you are not using speaker test which specifically output this signal to left channel of a stereo device, other alsa application playing mono file are playing to both left and right channel

Comment 4 GitLab Migration User 2018-07-30 10:37:31 UTC

-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/pulseaudio/pulseaudio/issues/536.

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