Comment 0 for bug 1380046

When switching the port to either headphone ports from the speaker port there is a loud pop in the headphones. When I am playing music through the speakers at 100% volume and then switch, I can hear the music at a very loud volume through the headphones for a fraction of a second before dropping to the proper headphones volume which is much lower. Even if I mute the output before switching ports there is still a pop although not nearly as loud.

I believe this is a driver issue (oxygen/virtuoso). The Essense STX uses a relay to switch between the speaker and headphones ports. I am guessing the the power for the speaker (line out) port is much higher than that used for the headphones port and the drivers need to mute the sound at a hardware level before switching to elmininate the pop. On Windows when switching to and from speaker and headphones port the output would be muted for almost a second as the port was switched so there was no pop. On Ubuntu there is no delay when switching ports. I have looked at the driver source code and there is an anti_pop_delay of 800 milliseconds used on the Xonar init method. I think this same delay should probably be added when switching to the headphone ports.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: alsa-base 1.0.25+dfsg-0ubuntu4
ProcVersionSignature: Ubuntu 3.13.0-37.64-generic 3.13.11.7
Uname: Linux 3.13.0-37-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.14.1-0ubuntu3.5
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC2: michael 20842 F.... pulseaudio
 /dev/snd/controlC0: michael 20842 F.... pulseaudio
 /dev/snd/pcmC0D0p: michael 20842 F...m pulseaudio
 /dev/snd/controlC1: michael 20842 F.... pulseaudio
CurrentDesktop: Unity
Date: Sat Oct 11 22:50:15 2014
InstallationDate: Installed on 2014-10-07 (3 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
PackageArchitecture: all
SourcePackage: alsa-driver
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:STX successful
Symptom_Card: HD Webcam C910 - USB Device 0x46d:0x821
Symptom_PulsePlaybackTest: PulseAudio playback test successful
Symptom_Type: None of the above
Title: [AV200 - Xonar STX, playback] Playback problem
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 08/20/2013
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 1401
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: P8H77-M PRO
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev X.0x
dmi.chassis.asset.tag: Asset-1234567890
dmi.chassis.type: 3
dmi.chassis.vendor: Chassis Manufacture
dmi.chassis.version: Chassis Version
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr1401:bd08/20/2013:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnP8H77-MPRO:rvrRevX.0x:cvnChassisManufacture:ct3:cvrChassisVersion:
dmi.product.name: System Product Name
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer