Windows 11 September 2026 Preview Update Causes Some Games and Apps to Crash
Microsoft has confirmed that some games and applications using AC-3, also known as Dolby Digital, audio decoding may crash after installing the Windows 11 September 2026 Preview Update, KB5124010.
KB5124010 can cause AC-3 audio-related application crashes
KB5124010 is an optional Windows 11 update that users must manually select and install. This should limit the number of potentially affected devices. However, the update may install automatically on Windows 11 24H2 systems when the option to Get the latest updates as soon as they’re available is enabled.
“In some cases, an application may fail to start or close without warning. In other cases, an application may function normally until a certain feature is used, such as playing music,” Microsoft said in a Friday update to the Windows Release Health Dashboard.
“Applications affected vary and may include games, media players, and certain productivity applications.”
Microsoft noted that many modern applications do not rely on Windows for AC-3 audio decoding and are therefore unaffected. The crash-causing components are most commonly used by legacy applications that depend on Windows’ built-in audio decoding. However, modern applications that support the legacy AC-3 codec often include their own audio decoding components.
Microsoft is working on a fix
Microsoft has not provided an estimated timeline for a fix. The company said it is working to resolve the issue and will provide more information in a future update.
Other recent Windows 11 audio and update issues
Last month, Microsoft released an emergency update to address another known issue that caused USB audio problems after users installed the September 2026 security updates KB5124008 and KB5124012. The emergency update also addressed Remote Desktop Services failures and Hyper-V issues.
Last year, Microsoft fixed a similar problem that caused audio playback failures and Code 10 errors on Windows 11 24H2 systems using USB audio device drivers. The company also removed a safeguard hold that blocked upgrades and caused Bluetooth headsets and speakers to malfunction on systems using Dirac audio improvement software.
Two years ago, an issue caused game audio to unexpectedly increase to maximum volume when users connected a USB DAC sound system. Microsoft also addressed a Blue Screen of Death (BSOD) problem that blocked Windows 11 24H2 upgrades on systems with incompatible Intel Smart Sound Technology (SST) audio drivers.
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Source: www.bleepingcomputer.com