By Greg Nowak. Last updated 2026-10-02.
A missing USB headset can interrupt a client call, a recording session, or a team's working day. The useful first question is where the device disappears: at the USB connection, in Linux audio hardware, or only in Kubuntu's sound settings. That answer determines the next step.
This guide is for Kubuntu 20.04. The original note also mentioned an old patch and hdajackretask. Both relate to particular analogue jack problems, so use the checks below before changing audio packages or installing an override.
Start with the connection
Unplug the device, connect it directly to another USB port, and test it without a dock or hub if possible. If it needs external power, check that too. Then run:
lsusbCompare the list before and after plugging it in. An entry that appears only when connected tells you the USB bus can see the hardware. If nothing changes, try the device on another computer. A cable, port, power, or device fault is more likely than a Kubuntu sound setting.
If USB detects it, ask ALSA whether it has a playback or recording device:
aplay -l
arecord -l
cat /proc/asound/cardsA headset may appear in both lists; a USB microphone may appear only under arecord -l. Note the device name rather than assuming it will always have the same card number. USB audio card numbers can change after reconnection or reboot.
| What you see | Likely next step |
|---|---|
Absent from lsusb |
Check the port, cable, hub, power, and device on another machine. |
In lsusb, absent from ALSA |
Check recent kernel messages and the USB audio driver. |
| In ALSA, absent from sound settings | Check the PulseAudio session and available devices. |
| Listed everywhere, but silent | Select the output or input, check mute and volume, then test the application. |
If ALSA cannot see the USB audio device
Reconnect it and inspect the most recent kernel messages with dmesg. Look for the device name, USB connection errors, or snd-usb-audio. You can also check whether the USB audio module is loaded:
lsmod | grep snd_usb_audioIf the module is absent, sudo modprobe snd-usb-audio is a reasonable temporary test. Run aplay -l or arecord -l again. If the device still does not appear, record the USB vendor and product ID from lsusb and the relevant kernel messages. Those details are more useful for diagnosing a hardware compatibility issue than repeatedly restarting the desktop audio service.
If ALSA sees it but Kubuntu does not use it
Open Kubuntu's audio settings and select the USB device for output or input. Check the relevant volume and mute controls, then check the calling or recording application's own device selection. Applications can keep a previously chosen device even after the system default changes.
For a closer look at the desktop audio server, run these as your normal signed-in user:
pactl info
pactl list short sinks
pactl list short sourcesSinks are outputs; sources are inputs. If the USB device is listed, the problem is usually selection, routing, or mute rather than detection. If pactl info cannot connect and pavucontrol stays at “Establishing connection to PulseAudio,” check the user session:
pulseaudio --check
pulseaudio --start
pactl infoThe original note used pulseaudio --check ; pulseaudio -D. The check is still useful, but its exit status needs interpretation; --start is the clearer command for starting a missing PulseAudio daemon. Run it without sudo. If it fails again, capture the error and investigate the session instead of treating a restart as a permanent fix.
What about the old patch and jack override?
The earlier article linked to a PPA for Launchpad bug #1869819. That bug concerned detection of a headset plugged into a Conexant analogue audio jack on certain HP machines. Ubuntu records the fix as released for 20.04. It is not a general USB audio fix, so do not add that old PPA simply because a USB headset is missing.
The earlier sudo apt install alsa-tools-gui and hdajackretask steps belong to a different branch of troubleshooting: an internal HDA headphone or microphone jack whose routing is wrong. If that is your actual problem, the tool lets you test a codec change with “Apply now” before choosing “Install boot override.” Its “Parser hints > jack_detect = no” setting should only be considered for a diagnosed jack detection issue, not applied to every audio fault. The tool also provides “Remove boot override” if a saved change causes trouble.
Make the fix last beyond today
Kubuntu 20.04 is based on Ubuntu 20.04, which ended standard support in May 2025. Ubuntu Pro can extend security maintenance, but an older installation may still be a poor place to troubleshoot newer USB hardware indefinitely. For a work machine, document the device ID, the failing layer, and the tested fix. Then plan and test an upgrade path through 22.04 before moving to 24.04, including a call or recording test with the actual USB device.
If audio trouble is holding up a team's work and you need someone to sort the immediate fault and the upgrade plan, get in touch with Greg.
Ubuntu 20.10: USB headphones found again after a PulseAudio restart
When the USB headset is visible to the kernel but not to the sound settings, restart PulseAudio for your user: pkill -U $USER pulseaudio (Launchpad bug #1865499).
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Need help with this kind of work?
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