#957 Strange Opus audio bug affecting at least 2 of our users.


This has been an ongoing problem with at least 2 of our users ever sense Opus was implemented. Our workaround is to force the server to use Celt though the overall sound is not near as good.

The server is Arch Linux 64 running the latest git snapshots and this problem still exists as of Feb 10 2013.

The clients are all Windows running current snapshots.

User 1: The most frequently affected has used multiple different MICs, headsets and has recently had to switch MOBO and CPU due to a recent MOBO failure. Sadly this didn't fix the problem. The problem also persists between windows 7 and 8. Next time he is in Linux I will test if he still has the problem. I'm attaching his dxdiag and an audio sample.

User 2: Affected far less often. Has nearly the same hardware as I. The only notable difference is he is running 3 AMD GPUs vs my one Nvidia GPU. He has recently switched from an M-Audio Producer USB Mic to a Logitech G930 and still the problem persists.

User 3: Me, not affected at all, other than the ear shattering pain... Only other notable differences from User 2 I can think of is I'm using a Killer 2100 Nic “Don't judge me I got it for free.” and i'm using a Blue Yeti MIC. I haven't had this problem in windows 7 8, Arch Linux 64 and FreeBSD 9.1.

1 Attachments


  • RED_404

    RED_404 - 2013-02-10

    Hmm can't add multiple files. Attached User1 dxdiag and audio sample.

    Some system info from the murmur server.
    OS: Arch Linux x86_64
    Hostname: salmac
    Uptime: 49 days, 6:35
    Kernel: 3.6.10-1-ARCH
    Shell: /bin/bash
    Packages: 326
    Window Manager: unknown
    RAM: 2466 MB / 7973 MB (30%)
    CPU: AMD FX(tm)-4100 Quad-Core Processor
    Boot: 31M / 464M (7%) (ext4)
    Root: 72G / 440G (18%) (ext4)

    Last edit: RED_404 2013-02-10
  • RED_404

    RED_404 - 2013-02-10

    IRC log for clarification.

    [10:26] <Ben_Mumble_com> RED-404: what is the problem? "Ear shattering pain" for the listeners?
    [10:27] <RED-404> yes check the sample file in User1.DxDiag&Flac.7z
    [10:28] <RED-404> its only with opus and every listener in the chan will hear it
    [10:29] <Ben_Mumble_com> I see
    [10:31] <DireFog> Sheesh that sounds like Metallica
    [10:32] <Ben_Mumble_com> "using opus, certain users appear to send sound that is "ear shattering pain" at random times: Is that description of the problem?
    [10:33] <RED-404> we'll all users I think the problem is on the broadcasters' side
    [10:34] <DireFog> does everything they say sound like that, or it it just for a while when they start talking?
    [10:35] <RED-404> one thing we were going to check is if it had something to do with cool & quiet. The CPU jumping frequencies from ~800 MHz to 2.4GHz
    [10:36] <DireFog> that shouldn't be a problem unless people are on really broken WinXP systems
    [10:36] <RED-404> and its not constant but its frequent
    [10:38] <Ben_Mumble_com> in the "ear shattering pain" do you hear voice at all?
    [10:39] <DireFog> so they get normal after a while without restarting the client?
    [10:40] <RED-404> I have a 6 min audio clip of him and he only does it one time and yes I hear voice sometime it lasts for 4 to 6 words and its still understandable
    [10:40] <RED-404> god I can't spell need sleep
    [10:41] <RED-404> and no it never normalizes or fixes itself it can be as frequent as every third word or as infrequent as not happening for 2hr
    [10:41] <DireFog> could you check if they have the maximum gain for AGC set really high? It could be an effect of extreme clipping hitting the CODEC
    [10:42] <DireFog> hum then it's rather something different
    [10:42] <Ben_Mumble_com> RED-404: I would submit this conversation with your bug report for further clarity
    [10:42] <RED-404> normally the gain is set between default and 1

  • Anonymous - 2013-04-03

    Wish you would have included the issue description in your initial report. I spent forever trying to find if a bug report was opened for this.

    We recently started using opus on our server and ever since then messages that my friend transmits have a small chance to cause ear shattering pain. Maybe once every 100 times he talks it does this, but when it happens it's like a bomb went off and my ears ring. It is seriously THAT LOUD which in my opinion makes this a very serious bug (potential for hearing damage). It's to the point where I cannot use Mumble with him anymore unless I don't use the headset, because it causes physical pain to my ears. If there is another user in the channel they hear it too. You can barely understand what they were trying to say in their transmitted message because it seems like the gain is set to +10000dB. Then the next thing they say will be at normal, human-safe volume.

    We are all using the latest snapshot. He is using windows 8 with his laptop's integrated Conexant audio with the latest drivers available.

    This never happened when it was using the old celt codec. Not even once.

  • chopster179

    chopster179 - 2013-09-24

    I can also confirm that we've had this issue on our Mumble server as well. Are there any updates on this issue?

  • Stefan H.

    Stefan H. - 2013-11-07
    • status: open --> closed
    • Version: --> unspecified

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