HDMI sound output only works if laptop monitor is on

[Øsse]

Binary package hint: xserver-xorg-video-ati

I'm using Ubuntu 10.10, fully updated from the regular repositories.

I connect my laptop to an HDTV through HDMI, configuring it through Preferences -> Monitors. I switch sound output to HDMI in System -> Preferences -> Sound -> Output. This works flawlessly as long as I somehow use my laptop monitor, meaning that I either mirror the screens or use an extended desktop. If I turn off the laptop monitor there is no sound output through the HDMI; turning back on the laptop monitor restores sound output to the TV. Switching back to the regular output device works as expected.

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: xorg 1:7.5+6ubuntu3
ProcVersionSignature: Ubuntu 2.6.35-24.42-generic 2.6.35.8
Uname: Linux 2.6.35-24-generic x86_64
Architecture: amd64
DRM.card0.HDMI_Type_A.1:
 status: disconnected
 enabled: enabled
 dpms: Off
 modes:
 edid-base64:
DRM.card0.LVDS.1:
 status: connected
 enabled: enabled
 dpms: On
 modes: 1920x1080 1680x1050 1400x1050 1280x1024 1440x900 1280x960 1280x854 1280x800 1280x720 1152x768 1024x768 800x600 848x480 720x480 640x480
 edid-base64: AP///////wAGr+0RAAAAAAETAQOAIhN4CsiVnldUkiYPUFQAAAABAQEBAQEBAQEBAQEBAQEBTDaAXnA4RkAeFKoAWMEQAAAYAAAADwAAAAAAAAAAAAAAAAAgAAAA/gBBVU8KICAgICAgICAgAAAA/gBCMTU2SFcwMSBWMSAKAE8=
DRM.card0.VGA.1:
 status: disconnected
 enabled: disabled
 dpms: Off
 modes:
 edid-base64:
Date: Mon Jan 3 02:40:35 2011
DkmsStatus:
 synaptics, 1.1.0, 2.6.35-24-generic, x86_64: installed
 synaptics, 1.1.0, 2.6.35-23-generic, x86_64: installed
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
Lsusb:
 Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
 Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 001 Device 005: ID 045e:0039 Microsoft Corp. IntelliMouse Optical
 Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: CLEVO W760/M770CU
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.35-24-generic root=UUID=0558c756-7152-43a4-963c-a15c39fa1697 ro quiet splash
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: xorg
dmi.bios.date: 10/26/2009
dmi.bios.vendor: Phoenix Technologies LTD
dmi.bios.version: CALPELLACRB.86C.0000.X.0000000000
dmi.board.asset.tag: Tag 12345
dmi.board.name: W760/M770CU
dmi.board.vendor: CLEVO
dmi.board.version: Not Applicable
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 9
dmi.chassis.vendor: CLEVO
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvrCALPELLACRB.86C.0000.X.0000000000:bd10/26/2009:svnCLEVO:pnW760/M770CU:pvrNotApplicable:rvnCLEVO:rnW760/M770CU:rvrNotApplicable:cvnCLEVO:ct9:cvrN/A:
dmi.product.name: W760/M770CU
dmi.product.version: Not Applicable
dmi.sys.vendor: CLEVO
glxinfo: Error: [Errno 2] No such file or directory
system:
 distro: Ubuntu
 codename: maverick
 architecture: x86_64
 kernel: 2.6.35-24-generic

[bugbot (bugbot)]

Hey Øsse,

Hi, have you had a chance to test if this bug is still present in natty?

If it does (and if you're the original reporter), please boot into natty
and run the command:

  apport-collect <bug-number>

which will update the bug with fresh logs and tag the bug as affecting
natty. (It is best to run this right after reproducing the problem.)

[bugbot (bugbot)]

We're closing this bug since it is has been some time with no response from the original reporter. However, if the issue still exists please feel free to reopen with the requested information. Also, if you could, please test against the latest development version of Ubuntu, since this confirms the bug is one we may be able to pass upstream for help.