Rumor has it that the my USB ports powered by an AMD chipset might be
the culprit. I have no clue whatsoever how this could be fixed in
software, but I am now waiting for a PCIe USB card with a different
chipset to check if there's a (preliminary) fix in hardware at least.

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https://bugs.launchpad.net/bugs/1927255

Title:
  [USB-Audio - RODECaster Pro, playback] Sound is distorted (20.04)

Status in alsa-driver package in Ubuntu:
  Confirmed

Bug description:
  I got a Rodecaster Pro USB device that has been causing trouble before
  and already lead to quirk handling in the kernel for the sample rate,
  see
  
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/sound/usb/format.c?h=v5.8#n412

  The Rodecaster is running fine on my laptop, but on my desktop, only
  audio input is working. The audio output is distorted. It's played
  kind of very slowly. Interestingly, if the source is a video file, the
  video plays slower, e.g. YouTube in a browser. I have never seen
  anything like that before.

  I have tried to figure out what the cause might be and I think I have
  reached the end of where I can get to on my own. I have documented
  most things at https://ubuntuforums.org/showthread.php?t=2461568

  Putting my last step it in a nutshell: I have booted both my computers
  with a plain Ubuntu 21.04 from a pen drive (it uses kernel version
  5.11.0-16-generic) to make sure it's not some different configuration
  that I have set up over the years on my systems (both Ubuntu 20.04
  with kernel 5.8.18). I attached the Rodecaster. It runs fine on my
  laptop, but not on my desktop (used the output test from).

  I then detected the card number with

  aplay -l

  I killed pulseaudio with

  pulseaudio -k

  I then played the same sample (encoded in 48000 Hz in PCM signed 32
  bit little endian format) using

  aplay -f S32_LE -c 2 -r 48000 -D hw:x ~/sample.wav

  where x is the appropriate card number and the rest of the arguments
  meet the Rodecaster's narrow specification. It's playing fine on the
  laptop, but distorted on the desktop. As far as I understand using
  aplay this way without a plugin should send the file directly to the
  device, so I assume there's something on the way from aplay to the
  Rodecaster that's interfering (kernel or even some piece of hardware)
  - and that definitely is where my expertise ends (rather a little
  before :-)).

  I'll gladly contribute any information that could be useful and I will
  willingly help to debug this problem if it may be related to the
  kernel. If there's anything I can do, please let me know.

  Cheers,
  Oliver

  ProblemType: Bug
  DistroRelease: Ubuntu 20.04
  Package: alsa-base 1.0.25+dfsg-0ubuntu5
  Uname: Linux 5.8.18-050818-generic x86_64
  NonfreeKernelModules: blackmagic_io nvidia_modeset nvidia
  ApportVersion: 2.20.11-0ubuntu27.16
  Architecture: amd64
  CasperMD5CheckResult: skip
  CurrentDesktop: ubuntu:GNOME
  CurrentDmesg: Error: command ['dmesg'] failed with exit code 1: dmesg: read 
kernel buffer failed: Operation not permitted
  Date: Wed May  5 18:28:46 2021
  InstallationDate: Installed on 2020-05-15 (355 days ago)
  InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
  PackageArchitecture: all
  SourcePackage: alsa-driver
  Symptom: audio
  Symptom_AlsaPlaybackTest: ALSA playback test through plughw:Pro failed
  Symptom_Card: RODECaster Pro - RODECaster Pro
  Symptom_Type: Digital clip or distortion, or "overdriven" sound
  Title: [USB-Audio - RODECaster Pro, playback] Sound is distorted
  UpgradeStatus: No upgrade log present (probably fresh install)
  dmi.bios.date: 10/30/2020
  dmi.bios.release: 5.17
  dmi.bios.vendor: American Megatrends Inc.
  dmi.bios.version: A.40
  dmi.board.asset.tag: To be filled by O.E.M.
  dmi.board.name: B550-A PRO (MS-7C56)
  dmi.board.vendor: Micro-Star International Co., Ltd.
  dmi.board.version: 1.0
  dmi.chassis.asset.tag: To be filled by O.E.M.
  dmi.chassis.type: 3
  dmi.chassis.vendor: Micro-Star International Co., Ltd.
  dmi.chassis.version: 1.0
  dmi.modalias: 
dmi:bvnAmericanMegatrendsInc.:bvrA.40:bd10/30/2020:br5.17:svnMicro-StarInternationalCo.,Ltd.:pnMS-7C56:pvr1.0:rvnMicro-StarInternationalCo.,Ltd.:rnB550-APRO(MS-7C56):rvr1.0:cvnMicro-StarInternationalCo.,Ltd.:ct3:cvr1.0:
  dmi.product.family: To be filled by O.E.M.
  dmi.product.name: MS-7C56
  dmi.product.sku: To be filled by O.E.M.
  dmi.product.version: 1.0
  dmi.sys.vendor: Micro-Star International Co., Ltd.

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