HDMI audio cuts out intermittently while normal audio plays fine

[Michael Rooney]

Binary package hint: pulseaudio

I have my audio set up to play through my laptop speakers and over HDMI to my television. In Jaunty this works fine while in Karmic the HDMI audio will intermittently cut out for a split second a few times a minute. During this time however the audio over the laptop speakers plays just fine. It just seems as if a frame of the HDMI audio gets dropped randomly. The video over the HDMI is perfectly fine, FYI.

ProblemType: Bug
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: michael 4942 f.... mixer_applet2
                      michael 7360 F.... npviewer.bin
 /dev/snd/pcmC0D0p: michael 7360 F...m npviewer.bin
 /dev/snd/timer: michael 7360 F.... npviewer.bin
Card0.Amixer.info:
 Card hw:0 'Intel'/'HDA Intel at 0xf6ffc000 irq 21'
   Mixer name : 'SigmaTel STAC9228'
   Components : 'HDA:83847616,10280209,00100402'
   Controls : 28
   Simple ctrls : 18
Date: Wed Jul 8 21:20:16 2009
DistroRelease: Ubuntu 9.10
NonfreeKernelModules: nvidia wl
Package: pulseaudio 1:0.9.15-4ubuntu1
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.30-10.12-generic
SourcePackage: pulseaudio
Uname: Linux 2.6.30-10-generic x86_64

[Luke Yelavich (themuso)]

Could you plesae try the new test version of PulseAudio in the ubuntu-audio-dev PPA? http://launchpad.net/~ubuntu-audio-dev/+archive

Thanks.

 affects ubuntu/pulseaudio
 status incomplete

[Michael Rooney (mrooney)]

Surely Luke, I've enabled that and upgraded and will get back to you,
thanks! Also, the "IEC958" switch seems to get reset on reboots (and
the "IEC958 Default PCM" gets set -- what exactly is that one?) or
something which makes this a little tedious to set up each time. If I
notice that that keeps happening I'll file a report for that as well.

[Michael Rooney (mrooney)]

After a restart I can only seem to get audio out of my laptop
speakers, even though IEC958 is enabled. I don't think this is a
regression from the upgrade though; I had this happen once or twice
before in Karmic where no matter what I do I can't seem to get audio
to go over HDMI for that session. It doesn't seen to be a deficiency
in any underlying process I am using as I've never experienced any of
these issues in Jaunty. Overall HDMI audio seems a little borked in
Karmic :)

[The Fiddler (stapostol)]

I am experiencing the exact same issue on Jaunty (amd64, nforce4 audio, nvidia 9500GT for hdmi & audio passthrough). I have created a "combined" Pulseaudio sink that directs audio to both the hdmi and analogue devices. While everything works perfectly on the analogue speakers, audio drops out intermittently on the hdmi connection (tested with xbmc 9.04.1). The issue is similar to the effect you get when you try to use an obsolete alsa application at the same time as pulseaudio - however, xbmc *should* be using pulse and the sound plays correctly on the analogue speakers.

Toggling the IE958 checkboxes in gnome-volume-control does not have any effect at all.

Attached is my /etc/pulse/default.pa, which is silghtly modified from a vanilla instaleld (I have added a "load-module module-alsa-sink" line for the hdmi device, which was not recognized by the hal module, plus set the hdmi device as default).

[Tristan Schmelcher (tschmelcher)]

I have the same problem, also on Jaunty, with a brand-new System76 Leopard Extreme. Graphics card is an NVIDIA GTX 275, and audio is an "HDA Intel - ALC889". HDMI sound periodically cuts out for half a second to a second. It doesn't happen all that often though, maybe every 5 minutes or so on average. It's not specific to PulseAudio though. I have reproed it with pure ALSA and also OSS! So it's either a low-level bug that's common to both ALSA and OSS, or it's a hardware bug. :( Or possibly a bug in the TV (mine is a SONY XBR4).

I'm opening this against the kernel since it occurs with both ALSA and OSS.

Note that I would use analog audio if I could, but I can't. The latest NVIDIA cards don't support turning off HDMI audio transmission, and my TV doesn't support selecting analog audio if an HDMI audio signal is present. Apparently lots are that way.

(P.S. I of course had to make the same changes to /etc/pulse/default.pa as The Fiddler in order to make PA recognize the Digital device.)

[The Fiddler (stapostol)]

Some more information: upgrading ALSA to 1.0.20 and Pulse to 0.9.15 didn't help with this issue. The only thing that seemed to make a difference were the "PCI latency" settings in my BIOS: higher values seemed to make the issue appear at a higher frequency; lower values seemed to improve - but not fix - the situation. (I tried 1, 2, 4, 8, 16, 32, 64, 128, 255, default is 32).

My final solution was to pop in an old SBLive! 5.1 card I happened to have lying around. This fixed the dropout issue completely (but caused different problems which cause Pulse to die completely every few minutes).

I don't think this issue is connected to the specific TV (I have a Sony W4000), as I have confirmed HDMI audio to work correctly with different hardware/software combinations.

[Leann Ogasawara (leannogasawara)]

@Tristan, I see you opened a task against the kernel kernel but appear to be running the older Jaunty kernel. Could you please test and confirm the issue remains with the newer 2.6.31 based Karmic kernel? Also as kernel bugs are typically hardware specific, if you have a soundcard and codec which differs from Michael (the original bug reporter), it would be best to open a new bug for now. Thanks.

[Michael Rooney (mrooney)]

As the original reporter of this bug, I can no longer reproduce it;
HDMI audio has been working just fine since A6 and Beta. I never
experienced the issue in Jaunty, and the other person to confirm it
was there, so I'd say that is a different bug and this one can be
closed.

[Andy Whitcroft (apw)]

@Michael Rooney -- Thanks for that based on your feedback as submitter I will close this one off. If you are seeing HDMI issues still and did on Jaunty that sounds like a different cause so lets get a new bug opened for that.

[Michael Cook (michaelcook-mjc)]

FWIW I have a pretty similar experience in Meerkat 10.10. HDMI Audio from Zotac ION 330 when coming back from a resume or hibernation/standby there is a 0.5s gap of silence every 10-15 seconds contsistently.

I've read a few things about how to fix this, the one that seemed to help most people was due to the screen-detection in xorg.conf but specifying the monitor made no difference for me. I mention it because maybe something is trying to detect HDMI audio capabilities every 15seconds.

With regular audio there are no gaps/drops. I can't use regular audio and HDMI signal with my reciever and graphics in Ubuntu meerkat and my HDTV are screwed up. So far, all I've learnt is to not have bothered upgrading since 8.04 would have saved me many hours of hassles. Appreciate anyone who can point me to a solution. ;o)

[Dee Winthrop (deewi)]

For the record I have the same problem on a Huawei Matebook Pro using Ubuntu 20.04 - fully upgraded. But the computer uses an HDMI adapter. Could that be the problem?

Again for the record, on another computer with Ubuntu 21.04 (Waylabd), everything works fine.

[Daniel van Vugt (vanvugt)]

This bug has been closed for 12 years. Please open a new one if you have any ongoing issues.