Public bug reported:
This is a complicated thing. I have a very specific problem with audio
output on HDMI.
I want to use an older notebook with Lubuntu 20.04 as a video source for
libreoffice slides, videos etc. to feed them over HDMI into a Blackmagic
Design ATEM Mini Pro ISO (video mixer) as one input. Configured on the
desktop just like a second screen or beamer.
Video works well and rock-stable, no problem at all.
But not audio.
Although I carefully configured audio with pavucontrol to be directed to
the HDMI output, the ATEM switcher does not recognize it as an audio
source (like when connecting a digital camera) and does not receive or
indicate any audio input.
Note:
But when I use the very same computer, same HDMI cable, same video with
a cheap chinese portable LCD screen with speakers (i.e. pull the cable
from the ATEM and plug it into the screen) it immediately starts playing
both video and audio. So there is evidence that the ubuntu notebook
definitely passes it's sound to HDMI and there's really an audio signal
on the HDMI.
I've opened a bug at Blackmagic Design, and got their reply that they
can't help and have never heard of such a problem before. Their guess is
that the linux notebook is not setting EDID configuration correctly and
thus not recognized by the ATEM, while the cheap LCD screen propably
does not care about EDID and just plays everything, therefore a wrong
EDID information would not matter.
Although I have decades of experience with Linux, I am not too familiar
with details of HDMI and the internals of the X11 driver, so I'm not
sure where to start debugging, not even, whether this is a problem of
Xorg/X11 or pulseaudio.
I've checked this with another notebook with much more recent (intel)
hardware, which offers dozens of HDMI audio options in the pavucontrol
selection menu, but same problem: Video works, but the ATEM does not
recognize it as a audio source.
Blackmagic Design (they're good in Windows and MacOS, but not Linux)
recommended to use an edid manager, whatever this means.
ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: xorg 1:7.7+19ubuntu14
ProcVersionSignature: Ubuntu 5.4.0-58.64-generic 5.4.73
Uname: Linux 5.4.0-58-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.14
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CasperMD5CheckResult: skip
CompositorRunning: None
CurrentDesktop: LXQt
Date: Thu Jan 7 13:16:26 2021
DistUpgraded: Fresh install
DistroCodename: focal
DistroVariant: ubuntu
DpkgLog:
ExtraDebuggingInterest: Yes
GraphicsCard:
Intel Corporation 2nd Generation Core Processor Family Integrated Graphics
Controller [8086:0106] (rev 09) (prog-if 00 [VGA controller])
Subsystem: Acer Incorporated [ALI] 2nd Generation Core Processor Family
Integrated Graphics Controller [1025:0742]
InstallationDate: Installed on 2020-05-16 (235 days ago)
InstallationMedia: Lubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
Lsusb:
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 04f2:b336 Chicony Electronics Co., Ltd
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Acer AO756
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-58-generic
root=UUID=a69345e2-b61e-4d25-baab-b23f75273af6 ro quiet
cryptdevice=UUID=d132b97b-f47a-4432-88b5-42aca187b9ff:luks-d132b97b-f47a-4432-88b5-42aca187b9ff
root=/dev/mapper/luks-d132b97b-f47a-4432-88b5-42aca187b9ff
resume=/dev/mapper/luks-d132b97b-f47a-4432-88b5-42aca187b9ff splash vt.handoff=7
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/19/2012
dmi.bios.vendor: Acer
dmi.bios.version: V1.05
dmi.board.asset.tag: Type2 - Board Asset Tag
dmi.board.name: Mimic
dmi.board.vendor: Acer
dmi.board.version: Type2 - Board Version
dmi.chassis.type: 10
dmi.chassis.vendor: Acer
dmi.chassis.version: V1.05
dmi.modalias:
dmi:bvnAcer:bvrV1.05:bd07/19/2012:svnAcer:pnAO756:pvrV1.05:rvnAcer:rnMimic:rvrType2-BoardVersion:cvnAcer:ct10:cvrV1.05:
dmi.product.family: Type1Family
dmi.product.name: AO756
dmi.product.sku: Type1Sku0
dmi.product.version: V1.05
dmi.sys.vendor: Acer
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.101-2
version.libgl1-mesa-dri: libgl1-mesa-dri 20.0.8-0ubuntu1~20.04.1
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.20.8-2ubuntu2.6
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:19.1.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel
2:2.99.917+git20200226-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.16-1
** Affects: xorg (Ubuntu)
Importance: Undecided
Status: New
** Tags: amd64 apport-bug focal ubuntu
--
You received this bug notification because you are a member of Ubuntu-X,
which is subscribed to xorg in Ubuntu.
https://bugs.launchpad.net/bugs/1910537
Title:
incorrect audio-EDID on HDMI, blocking audio transmission over HDMI
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1910537/+subscriptions
_______________________________________________
Mailing list: https://launchpad.net/~ubuntu-x-swat
Post to : ubuntu-x-swat@lists.launchpad.net
Unsubscribe : https://launchpad.net/~ubuntu-x-swat
More help : https://help.launchpad.net/ListHelp
