• Bug#1108496: linux-image-6.12.30+bpo-amd64: USB audio glitches: retire_

    From Ben Hutchings@21:1/5 to Jamie Forth on Wed Jul 9 15:00:01 2025
    XPost: linux.debian.kernel

    Control: tag -1 moreinfo

    On Sun, 2025-06-29 at 19:13 +0100, Jamie Forth wrote:
    [...]
    There are no differences in default ALSA parameters running under 6.1
    or 6.12 kernels.

    $ cat /proc/asound/USB/pcm0c/sub0/sw_params

    You mean "hw_params", right?

    access: MMAP_INTERLEAVED
    format: S32_LE
    subformat: STD
    channels: 10
    rate: 48000 (48000/1)
    period_size: 128
    buffer_size: 32768

    $ cat /proc/asound/USB/pcm0c/sub0/sw_params

    tstamp_mode: ENABLE
    period_step: 1
    avail_min: 128
    start_threshold: 9223372036854775807
    stop_threshold: 32768
    silence_threshold: 0
    silence_size: 0
    boundary: 4611686018427387904

    But these are for the capture side (pcm0c), whereas I thought the
    problem was with playback (pcm0p)?

    [...]
    The additional IRQs listed under the 6.12 kernel don't appear to
    exist, only irq/155-xhci_hcd in this case.

    They exist and have been allocated but are not used. The XHCI PCI
    driver can currently allocate multiple IRQs but only installs an IRQ
    handler for the first one. This is a bit strange but should not cause a problem because it also doesn't configure the hardware to use the
    additional IRQs.

    [...]
    ** Loaded modules:
    [...]
    nvidia_drm(POE)
    nvidia_modeset(POE)
    nvidia(POE)
    [...]

    I see some reports that the Nvidia proprietary drivers can cause latency
    spikes that affect audio. Can you please test whether this problem
    still occurs when using the nouveau driver instead?

    Ben.

    --
    Ben Hutchings
    73.46% of all statistics are made up.

    -----BEGIN PGP SIGNATURE-----

    iQIzBAABCgAdFiEErCspvTSmr92z9o8157/I7JWGEQkFAmhuZT8ACgkQ57/I7JWG EQlzhBAA0c8NHNJgCBOwsjMVgjOOpspR1k88OFpcl18MYj+gpXXZ8OtVCrs/vtGO uTAaBXixOH74xzToIs+3S+iyfaKSzPuTpM9tHdagKWxGA4N+7VpaaFcKdbC6cX8S N09iTFk4u0GOLEP8fDb8h5f7HGyh30yDQEuHGFoquS54iCqrcsrhyXF6dfFA4txp W5bfkJQ/ssPs6RuO+B0VY1hL7kUL8Bsnu0uyP06Hirk6RyHlxF8rAZmmLgT2BQnC 4f4jGkMXbjlWslaCeBNFzT66f6R7hHMwt8T9iJOyGXkXutlwg0M9jhl0uNJsFKMs 6H3UJBacElFd3f9fNlHlYBihsi5D29cbXd2D9nBgupDxOKhPDmZuosaIMMVjdVvB h9aJsu7OzVK7T4OFU/cMgB0jKKBg4haxtntfI06uf7m7SJlfA/rm4baWcNiLKDo4 rHmbINlDh2jrRWtQU0zUv+KVPAuRivQTSitKEGwXBp9Tk/udwPN00OtgVAcLYbJH 5OQYYMdBNTzMu8iVXwmu1QC0kjJPdtraqRF2KIY1LvXKfOkzjvFDBqCAeJoYOvlZ 5mVi9X1Zx4765i6+GvvFWQ5VkiBtDfGjHj/4eauSlAUhrZJ8sUbBRgHNNE5ftp3j F2oCZJgcA9nBYzpamRY63fzysj+iIGNULkg4H1szASD9pJ/4yU4=
    =kAow
    -----END PGP SIGNATURE-----

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)