Symptoms & scope
- An interface works at one rate but fails when an application requests another.
- The kernel reports cannot set freq or an invalid clock source.
Relevant environment
USB Audio Class interfaces using snd-usb-audio, including devices with external word clock or digital sync inputs.
Recognizable messages (synthetic examples)
usb 1-2: 1:1: cannot set freq 48000 (v2/v3): err -22Compare advertised rates, selected clock and control-transfer context; this is not enough to identify one firmware bug.
usb 1-2: clock source 41 is not valid, cannot useCheck missing external synchronization and model-specific behavior before disabling any validation.
Possible causes
These are possible explanations, not a confirmed diagnosis. Several independent faults can coexist.
- The selected rate or channel layout may not match the interface’s advertised alternate setting.
- An external clock may be missing or unlocked; device firmware or USB control-transfer faults can produce similar errors.
Diagnose safely
Run one command at a time in the relevant session. Read the explanation first. Uppercase placeholders need your own values; tools and privileges vary by distribution. These commands are displayed here and never executed by the website.
Check 1
Replace card0/stream0 with the stream file for the USB interface. Read ALSA’s advertised formats and rates; no PCM is opened.
cat /proc/asound/card0/stream0Interpret the result: Use the relevant playback or capture interface’s rates and channel counts. Advertised formats do not prove external clock lock or firmware correctness.
Check 2
Read USB-audio and controller events near the rate change; journal access may require privileges.
journalctl -k -b --no-pager -n 250Interpret the result: Invalid clock and set-frequency failure are distinct from xruns under load. USB disconnect/reset events suggest a transport check before audio tuning.
Evidence-guided next steps
Match the supported rate and clock source
If the requested rate is unsupported or external sync is absent, close active audio clients, select a documented supported rate and a valid internal or locked external clock in the interface controls. Restart the affected stream and compare.
Precautions: Changing clock affects all channels and can disrupt connected digital equipment. Record the original rate and sync source.
Recovery / rollback: Restore the previous rate and clock source if the interface or connected equipment loses synchronization.
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Compare USB transport or documented firmware fixes
If a valid supported clock/rate still fails and logs contain USB resets, compare a known-good direct cable/port after ending streams. If the fault is rate-specific without transport loss, review vendor firmware and kernel quirks for the exact interface model.
Precautions: Do not globally force 192 kHz or disable clock validation. Firmware updates need stable power and vendor recovery instructions.
Recovery / rollback: Restore the recorded port/cable or remove the single experimental configuration fragment. Firmware recovery depends on the vendor.
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References & review
This guide was prepared from primary project or distribution sources and reviewed on the date shown. This is an editorial source check, not evidence that a fix was reproduced on your hardware. Diagnostic log examples are synthetic fixtures. Version-dependent details must be checked against your installed release.
- Linux USB audio sample-rate and clock-source source (upstream implementation; behavior can vary by version)
- WirePlumber: ALSA configuration (project or distribution documentation)
- PipeWire: pipewire-props(7) (project or distribution documentation)
Related hardware and driver context
These profiles explain relevant driver paths. They do not establish that your device has this fault. Identify your device and binding first.
Identify hardware locally