The problem was caused by an incorrect configuration of the HDMI receiver (left-mono).
** Changed in: alsa-driver (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to alsa-driver in Ubuntu. https://bugs.launchpad.net/bugs/1222375 Title: [System Product Name, Nvidia MCP79/7A HDMI, Digital Out, HDMI] Playback problem Status in “alsa-driver” package in Ubuntu: Invalid Status in “pulseaudio” package in Ubuntu: Invalid Bug description: HDMI-Stereo output plays front-left to both speakers and front-right is inaudible. The system used to work perfectly with 10.04 LTS 32-bit. ProblemType: Bug DistroRelease: Ubuntu 12.04 Package: alsa-base 1.0.25+dfsg-0ubuntu1.1 ProcVersionSignature: Ubuntu 3.8.0-30.44~precise1-generic 3.8.13.6 Uname: Linux 3.8.0-30-generic x86_64 NonfreeKernelModules: nvidia AlsaVersion: Advanced Linux Sound Architecture Driver Version k3.8.0-30-generic. ApportVersion: 2.0.1-0ubuntu17.4 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: hafnagel 1764 F.... pulseaudio Card0.Amixer.info: Card hw:0 'NVidia'/'HDA NVidia at 0xfae78000 irq 23' Mixer name : 'Nvidia MCP79/7A HDMI' Components : 'HDA:10ec0888,104382fe,00100101 HDA:10de0007,10438356,00100100' Controls : 57 Simple ctrls : 22 Date: Sun Sep 8 12:21:39 2013 InstallationMedia: Ubuntu 12.04.3 LTS "Precise Pangolin" - Release amd64 (20130820.1) MarkForUpload: True PackageArchitecture: all ProcEnviron: TERM=xterm PATH=(custom, no user) LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: alsa-driver Symptom: audio Symptom_AlsaPlaybackTest: ALSA playback test through plughw:NVidia failed Symptom_Card: Built-in Audio - HDA NVidia Symptom_Jack: Digital Out, HDMI Symptom_Type: None of the above Title: [System Product Name, Nvidia MCP79/7A HDMI, Digital Out, HDMI] Playback problem UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 05/21/2009 dmi.bios.vendor: American Megatrends Inc. dmi.bios.version: 0514 dmi.board.asset.tag: To Be Filled By O.E.M. dmi.board.name: P5N7A-VM dmi.board.vendor: ASUSTeK Computer INC. dmi.board.version: Rev 1.xx dmi.chassis.asset.tag: Asset-1234567890 dmi.chassis.type: 3 dmi.chassis.vendor: Chassis Manufacture dmi.chassis.version: Chassis Version dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0514:bd05/21/2009:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnP5N7A-VM:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion: dmi.product.name: System Product Name dmi.product.version: System Version dmi.sys.vendor: System manufacturer To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1222375/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp