skype occasionally makes constant crackling / humming sound until restarted or pulseaudio killed

[James Hunt]

Occasionally my Lenovo t440s starts to make a constant crackling / humming sound. This doesn't stop sound from being played, but if no sound is playing, the noise persists.

As it's a new laptop, I thought it might be a hardware issue. It almost sounds like a bad earth connection.

However, the culprit seems to be pulseaudio since killing it and restarting solves the problem.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: pulseaudio 1:4.0-0ubuntu11
ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
ApportVersion: 2.14.1-0ubuntu3
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: james 2843 F.... pulseaudio
 /dev/snd/pcmC1D0p: james 2843 F...m pulseaudio
 /dev/snd/controlC0: james 2843 F.... pulseaudio
CurrentDesktop: Unity
Date: Fri May 2 09:09:37 2014
InstallationDate: Installed on 2014-04-11 (20 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Daily amd64 (20140409)
SourcePackage: pulseaudio
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/10/2014
dmi.bios.vendor: LENOVO
dmi.bios.version: GJET71WW (2.21 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20AQCTO1WW
dmi.board.vendor: LENOVO
dmi.board.version: 0B98405 STD
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvrGJET71WW(2.21):bd02/10/2014:svnLENOVO:pn20AQCTO1WW:pvrThinkPadT440s:rvnLENOVO:rn20AQCTO1WW:rvr0B98405STD:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 20AQCTO1WW
dmi.product.version: ThinkPad T440s
dmi.sys.vendor: LENOVO

[James Hunt (jamesodhunt)]

Note that the noise is heard when the laptop is connected on AC and on battery alone.

[James Hunt (jamesodhunt)]

Problem persists with all peripherals unplugged.

[James Hunt (jamesodhunt)]

diwic has identified the problem to be skype rather than pulse itself.

[Launchpad Janitor (janitor)]

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

[Franck78 (fbourdonnec)]

Hello,
second try, second fail ! bad....

Machine 1: absolute fresh install 14.04/64bits
-start and stop skype, 90% no sound at all. 10% perfect sound, 10% continuous buzzer.
-added supposed 32 bits lib support : nothing change
-removed package debian skype4.2
-tried every other package available on microsoft download : still no sound or buzzer.
-video working

Machine 2 : upgrade from 12.04 to 14.04 (32 bits)
-exact same no sound/buzzer

what do you need to solve this ?

Franck

[Vincas Dargis (talkless)]

Try to make sure that PULSE_LATENCY_MSEC=30 is in here:
sudo editor /usr/share/applications/skype.desktop

I've fixed Skype sound issues in two machines already (Ubuntu & Kubuntu) after upgrades. Skype/system changed in some way, but launcher file did not.

[Amr Ibrahim (amribrahim1987)]

Upgrading Skype to 4.3 may fix this (https://bugs.launchpad.net/ubuntu/+source/skype/+bug/1280109) as 4.3 adds support for pulseaudio 3.0 and 4.0.