USB Audio Broken After KB5124008? Fix the Code 10 Error

KB5124008, the September 8, 2026 security update for Windows 11, breaks some USB Audio Class 1.0 devices. Device Manager shows "This device cannot start (Code 10)" on the affected audio device, and volume controls stop responding or sit stuck at zero. Microsoft has confirmed the bug but has not shipped a fix yet. Switching the device to 2-channel stereo mode restores sound for most people.

If you installed this month's update and your USB headset, DAC, or audio interface suddenly went silent, you're not dealing with a loose cable or a dead device. This is a driver-level conflict introduced by the update itself, and it has a known workaround along with a few backup fixes if the workaround doesn't hold.

What Is Causing the USB Audio Bug After KB5124008?

KB5124008 changed how Windows 11 initializes USB Audio Class 1.0 devices on version 24H2 and later. The update conflicts with the multichannel audio driver path, so the device fails to start correctly and Windows falls back to an error state instead of loading the driver.

Microsoft's support documentation for this update lists it as a known issue: after installing the September 8, 2026 update, some USB Audio Class 1.0 devices might fail to start or produce audio. The bug is specific to build 26100.9445 (24H2) and 26200.9445 (25H2), which is the exact build number KB5124008 installs. USB Audio Class 2.0 devices, which most modern audio interfaces and higher-end headsets use, are not affected. Older and simpler devices, including cheap USB headsets, USB microphones, and basic DACs, are more likely to use Class 1.0 drivers and hit this bug.

To confirm you're on the affected build, open Settings > System > About and check the Build number under Windows specifications. If it reads 26100.9445 or 26200.9445, you have KB5124008 installed and your audio failure ties directly to this update rather than a coincidental driver issue.

How Do You Know If You're Hitting This Specific Bug?

Open Device Manager and look for a yellow warning icon on your audio device with error Code 10. If you see this exact code on a USB audio device right after installing KB5124008, you're hitting the update bug, not a driver conflict you introduced yourself.

Here's how to check:

• Press Windows key + X and select Device Manager.
• Expand Sound, video and game controllers.
• Look for your USB headset, DAC, or audio interface. A yellow triangle means Windows won't start it.
• Right-click the device and select Properties.
• On the General tab, check the Device status box. If it reads "This device cannot start. (Code 10)", you're hitting the known KB5124008 issue.

A second symptom shows up even without Code 10: the device works, but only in plain 2-channel stereo. If you try to switch it to 8-channel or 3D audio mode in Sound settings, it stops producing sound or the volume slider stops responding.

How Do You Fix USB Audio Not Working After KB5124008?

Set the affected device to 2-channel stereo mode. This is the workaround Microsoft and affected users have confirmed works, since the bug only breaks multichannel configurations on USB Audio Class 1.0 hardware.

Here's the exact sequence:

• Right-click the speaker icon in your taskbar and select Sound settings.
• Under Output, select the affected USB device, then click it to open its properties.
• Scroll down and select Device properties, then Additional device properties.
• Go to the Advanced tab.
• Under Default Format, choose a 2 channel, 16-bit option, such as "2 channel, 16 bit, 44100 Hz (CD Quality)".
• Click Apply, then OK.
• Unplug the USB device and plug it back in.

If Device Manager still shows Code 10 after this, the driver itself needs to reload:

• In Device Manager, right-click the affected device under Sound, video and game controllers.
• Select Uninstall device. Check the box for "Attempt to remove the driver for this device" if it appears, then confirm.
• Unplug the USB device.
• Restart your PC.
• Plug the device back in. Windows reinstalls the driver automatically, now starting in stereo mode by default in most cases.

What If the Device Still Won't Start?

Check for an updated driver directly from the manufacturer before touching Windows Update itself. Some audio hardware makers pushed driver updates within days of KB5124008, and those updated drivers avoid the conflict entirely.

• Go to your device manufacturer's support site (Focusrite, Behringer, Logitech, Razer, and similar brands all posted updates for affected models in September 2026).
• Search for your exact model number and download the current Windows 11 driver.
• Install it, then restart your PC.

Manufacturer driver pages usually organize downloads by product line rather than exact model number, so search the support site directly instead of relying on Windows Update to find it for you. Windows Update pulls generic drivers from Microsoft's catalog, and those generic drivers are the ones affected by the KB5124008 conflict. A vendor-specific driver package bypasses the generic driver path entirely.

If no updated driver exists yet, run the Windows built-in audio troubleshooter:

• Open Settings.
• Go to System > Sound.
• Scroll to Advanced and select Troubleshoot common sound problems.
• Follow the prompts and let it check your output device.

The troubleshooter won't fix the underlying KB5124008 bug, but it catches related issues like the wrong device set as default, which sometimes compounds on top of the Code 10 error.

Should You Uninstall KB5124008 to Get Sound Back?

Only as a last resort. Uninstalling the update removes September's security patches along with the fix for Teams and Outlook failing to launch on Arm64 PCs, a separate bug this same update resolved.

If you need audio working immediately and the 2-channel workaround does not help, here's how to remove it:

• Open Settings > Windows Update > Update history.
• Scroll down and select Uninstall updates.
• Find KB5124008 in the list and select Uninstall.
• Restart your PC when prompted.

Set a reminder to reinstall KB5124008 once Microsoft patches the USB audio issue, since staying on an older build long-term leaves known security holes open.

Key Takeaways

• KB5124008 (September 8, 2026) breaks some USB Audio Class 1.0 devices on Windows 11 24H2 and 25H2, showing Code 10 in Device Manager.
• Switching the device to 2-channel stereo mode in Sound settings restores audio for most affected devices.
• Uninstalling and reinstalling the audio driver clears the Code 10 error if the format change alone doesn't work.
• Check for a manufacturer driver update before removing KB5124008 entirely, since removing the update also removes this month's security patches.
• Microsoft has acknowledged the bug but has not released a permanent fix as of this writing.