Crackling sound after playing audio and suspended

[costales]

The Meizu MX4 is doing a weird "tic tic tic..." after receive a notification (from telegram, mail...) and it's suspended.

------

When I press the screen lock button on the MX4 shortly after playing music or ending a phone call I hear a radio/fuzzy distorted noise coming from the phone. To make it stop I need to unlock and lock the screen again but this is not ideal.

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When the screen is locked and the playing song is finished and waiting for a stopped signal, MX4 will do a weird lower sound.

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TEST CASE (Thanks to Kamikaze)
1. Boot the device and wait until it suspends (black screen)
2. ssh to the device
3. Run from the command line:
  $ aplay /usr/share/sounds/alsa/Front_Left.wav
4. Repeat step 3 until you reproduce the issue (3 to 5 times)

--- Original Case ---
How to reproduce (Note this does not always work, the phone needs to be in some specific state yet to be determined)

Ensure MX4 is not plugged into USB
Call the MX4 and hear the ringtone
Dismiss the call
Push the power button to turn off the screen
Tick Tick Tick
Push the power button to turn on the screen
hissing
Push the power button to turn off the screen
Tick Tick Tick
etc

It will not clear until you play another sound
Does not happen in silent mode of course

------from the dupe ----

Aquaris E4.5

Steps to reproduce:

1. Start playing a podcast.
2. Switch to a different app.
3. Lock the screen.
4. Wait for the Podcast to finish.
5. Wait a bit longer.

Expected results:

No noise from speaker.

Actual results:

Soft white noise from speaker. It seems that some part of the audio subsystem is still switched on. I am concerned that this could be draining battery.

Workaround:

After the Podcast finishes, unlock the phone and switch back to the Podbird app. This causes the noise to stop.

Comments:

I noticed the same soft white noise continues a second or two after the phone plays any sound from any app, but then turns off. I presume there is some time out turning off some part of the audio subsystem. Presumably if there is a reason, it should happen even when the app causing the sound to play is not active.

[Sebastien Bacher (seb128)]

the settings are a configuration ui, they are not involved in messaging sound or sound changes

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Cheng Lu (dawndiy)]

I wrote a music App with QtMultimedia.MediaPlayer. When the screen is locked and the playing song is finished and waiting for a stopped signal, MX4 will do a weird lower sound.

[Pat McGowan (pat-mcgowan)]

YC can you try to reproduce

[Yuan-Chen Cheng (ycheng-twn)]

@elsa, can you ask ethan to reproduce ?

[Ethan Chang (ethan.chang)]

I can hear a slight crack sound while playing music then turn screen off and also when the song ends.
It's a slight crack sound but when you are in a quite room you will notice the crack sound.

[Ari Salonen (ari-salonen)]

Same bug is happening after i receive telegram or text message.

[costales (costales)]

> Same bug is happening after i receive telegram or text message.

Yes, that is happening me. This bug is after OTA7 yet.

[Dylan Coakley (dylan-coakley)]

This bug has been reported in July 2015. Hasn't even been assigned to a milestone yet?? Its really annoying and should be more of a priority than other bugs. This happens after anything to do with audio meaning it affects all users and annoys all users. Not exactly giving a good first impression of Ubuntu OS.

[Pat McGowan (pat-mcgowan)]

I can hear a slight crackle snapping sound as described some of the time but its very faint
Perhaps we are not turning off the audio codec correctly on suspend?
(On the BQ I hear some white noise for around 3 secs even without suspending but no crackling)

[costales (costales)]

Hi @Pat: For me it's happening only in my MX4, my BQ E4.5 hasn't this problem.
And this bug is very annoying for me.
A hug.

[Dylan Coakley (dylan-coakley)]

Hi Pat - Thanks for assigning this and apologies if I came across as grumpy. This bug just really grinds my gears. :)
Many hugs.

[Pat McGowan (pat-mcgowan)]

@yc any updates?

[Dylan Coakley (dylan-coakley)]

Just so ye know this happens after every single phone call is ended. When audio is ended the OS doesn't seem to stop trying to output audio even if no audio is to be played.

[Marco Graziotti (graziottimarco)]

Same problem for me, on my Meizu MX4 (OTA-8), when I receive a notification, after the ring tone, I can hear a little sound from the speaker (like a continuous "tic", it seems a current discharge, or something similar).
It stops when I resume the phone from the standby mode.

[Andrea Bernabei (faenil)]

any update on this?

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Pat McGowan (pat-mcgowan)]

Lets take a closer look this week

[Pat McGowan (pat-mcgowan)]

could be related to bug #1518122

[Kamikaze (mick-saunders)]

Also affected. I can reproduce this perhaps near 50% of the time by opening a terminal and running:
aplay /usr/share/sounds/alsa/Front_Left.wav
And immediately on pressing enter turning the screen off.

You should do this somewhere reasonably quiet and you will hear the crackle/static/hissing sound a few seconds after the sound finishes.

[Martyn Lloyd-Kelly (martynlloydkelly)]

Not sure if this gives any of the devs a clue as to what may be happening but the unlock/lock fix doesn't work if you do it very quickly. It does work if you leave the phone unlocked for (roughly) 5 seconds before locking again; OS resource timing issue? I have an Meizu MX4 too.

[David Henningsson (diwic)]

I don't think this is PulseAudio. It's probably something in the kernel or the Android HAL.

Anyway, after PulseAudio has been playing a sound, there is a five second timeout until PulseAudio closes the hw stream. Or put it another way, PulseAudio plays back five seconds of silence after every sound (assuming there's nothing else that wants to play).
So it makes some sense that doing things within five seconds after a sound has stopped may cause a different chain of events.

[Morgan (z-admin-angels-gmail-com)]

Hello,

I confirm this bug, I use Aquaris E5HD. I often listen podcast (it's help me to fall in sleep).

The night I listen podcast and the morning I wake up and my batterie has been drained by ~ 20/30%.

It's very anoing !

[John McAleely (john.mcaleely)]

@z-admin-angels-gmail-com - are you saying it makes a brief ticking noise after playing a podcast? And would you know, if you are asleep? :-)

Otherwise this sounds like a different bug

[Dylan Coakley (dylan-coakley)]

Why is this bug being removed from the milestone?

[John McAleely (john.mcaleely)]

Because work on it has not completed in time for the milestone release.

On 21 March 2016 at 12:03, Dylan Coakley <email address hidden> wrote:

> Why is this bug being removed from the milestone?
>
> --
> You received this bug notification because you are a bug assignee.
> https://bugs.launchpad.net/bugs/1477838
>
> Title:
> Crackling sound after playing audio and suspended
>
> Status in Canonical System Image:
> Triaged
> Status in pulseaudio package in Ubuntu:
> Confirmed
>
> Bug description:
> The Meizu MX4 is doing a weird "tic tic tic..." after receive a
> notification (from telegram, mail...) and it's suspended.
>
> ------
>
> When I press the screen lock button on the MX4 shortly after playing
> music or ending a phone call I hear a radio/fuzzy distorted noise
> coming from the phone. To make it stop I need to unlock and lock the
> screen again but this is not ideal.
>
> -----
>
> When the screen is locked and the playing song is finished and waiting
> for a stopped signal, MX4 will do a weird lower sound.
>
> -----
>
> TEST CASE (Thanks to Kamikaze)
> 1. Boot the device and wait until it suspends (black screen)
> 2. ssh to the device
> 3. Run from the command line:
> $ aplay /usr/share/sounds/alsa/Front_Left.wav
> 4. Repeat step 3 until you reproduce the issue (3 to 5 times)
>
> --- Original Case ---
> How to reproduce (Note this does not always work, the phone needs to be
> in some specific state yet to be determined)
>
> Ensure MX4 is not plugged into USB
> Call the MX4 and hear the ringtone
> Dismiss the call
> Push the power button to turn off the screen
> Tick Tick Tick
> Push the power button to turn on the screen
> hissing
> Push the power button to turn off the screen
> Tick Tick Tick
> etc
>
> It will not clear until you play another sound
> Does not happen in silent mode of course
>
> ------from the dupe ----
>
> Aquaris E4.5
>
> Steps to reproduce:
>
> 1. Start playing a podcast.
> 2. Switch to a different app.
> 3. Lock the screen.
> 4. Wait for the Podcast to finish.
> 5. Wait a bit longer.
>
> Expected results:
>
> No noise from speaker.
>
> Actual results:
>
> Soft white noise from speaker. It seems that some part of the audio
> subsystem is still switched on. I am concerned that this could be
> draining battery.
>
> Workaround:
>
> After the Podcast finishes, unlock the phone and switch back to the
> Podbird app. This causes the noise to stop.
>
> Comments:
>
> I noticed the same soft white noise continues a second or two after
> the phone plays any sound from any app, but then turns off. I presume
> there is some time out turning off some part of the audio subsystem.
> Presumably if there is a reason, it should happen even when the app
> causing the sound to play is not active.
>
> To manage notifications about this bug go to:
>
> https://bugs.launchpad.net/canonical-devices-system-image/+bug/1477838/+subscriptions
>

[Dylan Coakley (dylan-coakley)]

Thanks John, do ye guys have a fix in mind for this?

Its one of those frustrating bugs. Gets on my nerves daily.

[John McAleely (john.mcaleely)]

Not yet - our initial investigations have not turned up a fix. I've put it on the list for 11

[John McAleely (john.mcaleely)]

"I noticed the same soft white noise continues a second or two after the phone plays any sound from any app, but then turns off. I presume there is some time out turning off some part of the audio subsystem. Presumably if there is a reason, it should happen even when the app causing the sound to play is not active."

So, I believe pulseaudio, by design, maintains active status briefly (ie a second or two) when a connection from an app terminates, so that if two sounds a played back to back there is continutity for the underlying hardware.

I think that's a separate bug (and possibly by design) than an annoying noise happening, which seems to be MX4 specific.

Sadly, so far, finding people with the deep knowledge of the android underpinnings of MX4 is proving tricky.

[Robie Basak (racb)]

This isn't MX4 specific. I'm affected and I have an Aquaris 4.5. See duplicate bug 1445527. My issue is not the noise itself, it is that it doesn't stop if the screen is off when music finishes and that this causes battery drain. If this isn't what you want to track in this bug, then please undupe my bug.

[costales (costales)]

> than an annoying noise happening, which seems to be MX4 specific.

@John: I have Nexus4, BQ E4.5 & MX4 and this is happening only in MX4.
FYI, I flashed this week the MX4 and set the default notification
sound, but same weird sound.

A hug.

[Jonas (jonny-boy)]

I don't know if it is relevant, but I use whatsappweb with lifecycle exception and both my mx4 and my m10 play the tick sound all the time, as soon as I turn the screen off.