[USB-Audio - Shokz Loop110, playback] Input and Duplex not listed, Output has underruns, dropouts for a few seconds then no sound

[Marcel Brouillet]

I purchased a USB dongle that presents to the system a sound device (and hides a Bluetooth or proprietary RF connection to a headset). https://fr.shokz.com/products/dongle

When connected, I only get to choose between two playback profiles in pavucontrol (see below). There is no input profile nor the Duplex that I'd expect.
Moreover, when I play some music, there are a few low cracks, music is barely recognizable for 2 seconds (if anything) and then fades out completely.
Sound is perfect with the same headset in Bluetooth mode A2DP or HFP, but I expected better latency with the proprietary USB dongle.

$ pactl list
Card #3
 Name: alsa_card.usb-Qualcomm_Shokz_Loop110_F521F7FD67FC2D2D69C7-02
 Driver: module-alsa-card.c
 Owner Module: 26
 Properties:
  alsa.card = "2"
  alsa.card_name = "Shokz Loop110"
  alsa.long_card_name = "Qualcomm Shokz Loop110 at usb-0000:00:14.0-13.1, full speed"
  alsa.driver_name = "snd_usb_audio"
  device.bus_path = "pci-0000:00:14.0-usb-0:13.1:1.2"
  sysfs.path = "/devices/pci0000:00/0000:00:14.0/usb1/1-13/1-13.1/1-13.1:1.2/sound/card2"
  udev.id = "usb-Qualcomm_Shokz_Loop110_F521F7FD67FC2D2D69C7-02"
  device.bus = "usb"
  device.vendor.id = "0a12"
  device.vendor.name = "Cambridge Silicon Radio, Ltd"
  device.product.id = "4007"
  device.product.name = "Shokz Loop110"
  device.serial = "Qualcomm_Shokz_Loop110_F521F7FD67FC2D2D69C7"
  device.string = "2"
  device.description = "Shokz Loop110"
  module-udev-detect.discovered = "1"
  device.icon_name = "audio-card-usb"
 Profiles:
  output:analog-stereo: Analog Stereo Output (sinks: 1, sources: 0, priority: 6500, available: yes)
  output:iec958-stereo: Digital Stereo (IEC958) Output (sinks: 1, sources: 0, priority: 5500, available: yes)
  off: Off (sinks: 0, sources: 0, priority: 0, available: yes)
 Active Profile: output:analog-stereo
 Ports:
  analog-output: Analog Output (type: Analog, priority: 9900, latency offset: 0 usec, availability unknown)
   Part of profile(s): output:analog-stereo
  iec958-stereo-output: Digital Output (S/PDIF) (type: SPDIF, priority: 0, latency offset: 0 usec, availability unknown

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 22.04.3 LTS
Release: 22.04
Codename: jammy

$ apt-cache policy alsa-base
alsa-base:
  Installed: 1.0.25+dfsg-0ubuntu7
  Candidate: 1.0.25+dfsg-0ubuntu7
  Version table:
 *** 1.0.25+dfsg-0ubuntu7 500
        500 http://archive.ubuntu.com/ubuntu jammy/main amd64 Packages
        500 http://archive.ubuntu.com/ubuntu jammy/main i386 Packages
        100 /var/lib/dpkg/status

System is up to date (apt update ; apt upgrade)

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: alsa-base 1.0.25+dfsg-0ubuntu7
ProcVersionSignature: Ubuntu 5.15.0-91.101-lowlatency 5.15.131
Uname: Linux 5.15.0-91-lowlatency x86_64
ApportVersion: 2.20.11-0ubuntu82.5
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: XFCE
Date: Tue Jan 9 10:21:29 2024
InstallationDate: Installed on 2023-02-13 (329 days ago)
InstallationMedia: Ubuntu-Studio 22.04.1 LTS "Jammy Jellyfish" - Release amd64 (20220809)
PackageArchitecture: all
SourcePackage: alsa-driver
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:Loop110 failed
Symptom_Card: Shokz Loop110 - Shokz Loop110
Symptom_Type: Underruns, dropouts, or "crackling" sound
Title: [USB-Audio - Shokz Loop110, playback] Underruns, dropouts or crackling sound
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/18/2021
dmi.bios.release: 5.17
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: UX582LR.203
dmi.board.asset.tag: ATN12345678901234567
dmi.board.name: UX582LR
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: 1.0
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTeK COMPUTER INC.
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrUX582LR.203:bd02/18/2021:br5.17:svnASUSTeKCOMPUTERINC.:pnZenBookProDuoUX582LR_UX582LR:pvr1.0:rvnASUSTeKCOMPUTERINC.:rnUX582LR:rvr1.0:cvnASUSTeKCOMPUTERINC.:ct10:cvr1.0:sku:
dmi.product.family: ZenBook
dmi.product.name: ZenBook Pro Duo UX582LR_UX582LR
dmi.product.version: 1.0
dmi.sys.vendor: ASUSTeK COMPUTER INC.
mtime.conffile..etc.modprobe.d.alsa-base.conf: 2023-03-02T20:23:08.273376