Microsoft has confirmed that its September 2026 Patch Tuesday update — KB5124008 — can leave some PCs completely silent, and it is the latest bug to pile onto an already shaky release.
- Status: Confirmed by Microsoft; no fix or patch is available yet, though a resolution is reportedly in development.
- Affected builds: Windows 11 25H2 (Build 26200.9445) and 24H2 (Build 26100.9445).
- KB article: KB5124008
- Error code: Device Manager reports “This device cannot start (Code 10)”
- Trigger: USB Audio Class 1.0 devices
What Windows 11 KB5124008 does to your audio
KB5124008 is the monthly security update rolling out to systems running Windows 11 25H2 or 24H2, bumping PCs to Build 26200.9445 or Build 26100.9445 respectively. You can verify which build you are on in Settings > System > About.
According to an updated support document spotted by Windows Latest, Microsoft now says some audio devices “might fail to start or produce audio” after installing recent Windows updates. If you are affected, your audio device simply will not work at all after booting — sometimes immediately following the reboot that applies the September update.
Turning up the volume won’t help, because Windows may not be able to start the device in the first place, so even at 100% volume you will get silence. Depending on how the staged rollout has reached your machine, the problem might not appear right away; if a related compatibility change hasn’t landed on your PC yet, you could run into it later unless Microsoft patches it.
Sound settings break, and the error code isn’t helpful
Microsoft warns that the Sound settings page may also become unresponsive, which makes troubleshooting from Settings difficult. Your next stop is Device Manager, where the affected audio device or driver reports:
“This device cannot start (Code 10).”
Uninstalling or disabling the driver won’t restore sound, because the problem originates from Windows Update rather than the driver itself. That is a common trap: users typically try to fix a Code 10 error by reinstalling the driver, but here the fault sits higher up the stack.
Microsoft specifically ties the confirmed issue to USB Audio Class 1.0 devices, but the problems aren’t limited to basic playback. One user reported that microphones can also stop working on affected devices.
Microphones and multichannel audio can drop out too
Even if your audio device starts normally, Windows may pick up an incorrect configuration. If you use multichannel features such as 3D audio or an 8-channel setup, you could suddenly lose sound.
As a temporary workaround, Microsoft recommends switching the affected device to 2-channel mode. If that doesn’t help, using different audio hardware is another option — and based on reports so far, wireless audio devices don’t appear to be affected.
Microsoft hasn’t provided a permanent workaround or patch, but it confirmed it is working on a resolution.
Other bugs piling up on KB5124008
The audio issue is far from the only problem. Windows Latest has documented several issues with KB5124008 since the September 8 rollout, including:
- Explorer.exe crashes that can leave you staring at a black screen.
- Broken File History backups.
- Problems with Claude Cowork and other apps that depend on Linux-based virtual machines.
- Remote Desktop issues.
- Reports of GPU problems on some AMD systems.
Microsoft has already acknowledged most of these. As for the audio bug, the company hasn’t tied it to any particular OEM, and based on the reports seen so far, it doesn’t appear limited to a single manufacturer. Given that this isn’t the first time a Windows update has broken audio, the issue could turn out to be wider than currently acknowledged.
What this means for you
If you haven’t installed KB5124008 yet, you can hold off. The staged rollout means you can wait for Microsoft to ship a fix without being forced into the update immediately.
If you’ve already updated and lost audio, temporarily switch your device to 2-channel mode or switch to different (ideally wireless) hardware until Microsoft patches the issue. Don’t waste time uninstalling the driver, since the fault comes from Windows Update, not the driver.
How to check if you’re affected
Open Settings > System > About and look for Build 26200.9445 (25H2) or Build 26100.9445 (24H2). If you see one of those builds and your sound has gone quiet, you are likely caught in the Windows 11 KB5124008 audio bug.
Source: Windows Latest
Build details:
- kb5124008
Over to you: If your PC hasn’t received the update yet, would you hold off until Microsoft ships a fix, or risk updating now?
