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Windows 10 (build 1803) usb audio start issue RRS feed

  • Question

  • -------------------------------------------------------------
    Windows 10 (build 1803) usb audio start issue:
    -------------------------------------------------------------

    Description:
    ---------------

    In rare cases, on PCs with only 1 root hub, opening the audio of a USB audio device can fail,
    if at the same time an external USB3 hub with lots of devices is being enumerated.

    1) The USB audio device is inserted into port #1.
    2) The USB hub containing lots of devices (network, other audio device) is
    inserted in port #2.
    3) The USB audio device is set as primary.
    4) The USB controller is a standard Intel USB3 root hub. Tested with various models
    and versions with the same result.

    It seem to be a problem on all Windows 10 versions including 1803.

    Symptom:
    ------------

    The symptom will be that it is possible to use the microphone on the USB audio device, but not the
    speaker.

    The audio subsystem will be full of outgoing PCM samples for the USB audio device, but no samples are
    ever sent to the device.

    It usually happens when resuming from suspend, but can also be
    reproduced by simply inserting the USB3 hub and the audio device at the same
    time (requires just the right timing by inserting the HUB a bit before the
    audio device).

    Analysis:
    -----------

    By inspecting the attached USB trace, the problem can be observed as the following:

    1) Normally when windows sees a USB audio device, it opens the audio briefly (or permanently if streaming),
    by switching the audio OUT interface from ALT-0 to ALT-1 or ALT-2 depending on bitdepth.

    2) In this rare case, the USB audio subsystem fails to send the ALT-1 or ALT-2, and never starts pushing ISO
    packets across the interface.

    The attached trace show several re-enumerations (and audio starts) that all go fine,
    and then the last one which fails.

    It seem like there are 2 real problems here:

    A) For some reason Windows decides that it cannot start the stream (bandwidth calculation?), and therefore never
    starts offloading audio packets.

    B) When A occurs, Windows fails to inform the upper layers that the audio device is dead. This causes upper-layer
    software (like browsers) to hang and misbehave. This is a side issue which only happens because of A, but one would
    expect that the operating system did not treat this case as a successfully opened audio device.

    Note1: It is not known if the external USB3 hub has anything to do with the issue, or if it just makes the problem
    easier to reproduce.

    Note2: By simply disabling the audio device and re-enabling it again solves
    the problem, and Windows correctly signals the ALT-1 or ALT-2 to the device
    and ISO packets start flowing.

    Thanks,

    Peter Dons Tychsen,

    Jabra R&D, GN Great Nordic

    Thursday, June 14, 2018 1:20 PM

All replies

  • The logs are here:

    https://www.dropbox.com/s/q199uvfxdio0suc/windows10-usb-audio-start.zip?dl=0

    The log can be viewed with Ellisys USB tracer software.

    Thursday, June 14, 2018 1:31 PM
  • Hell all,

    I would seem that there finally is a fix for this after lots of hard work with Microsoft.

    This fix is in this insider preview:

    https://blogs.windows.com/windowsexperience/2018/11/14/announcing-windows-10-insider-preview-build-18282/

    The fix is not verified yet, but for now it looks good.

    Thanks for all at Jabra & Microsoft for putting in the time to fix this.

    Thanks,

    Peter Dons Tychsen,

    Jabra R&D, GN Great Nordic

    Wednesday, November 21, 2018 5:14 PM