Microsoft says Windows 11 preview update can crash some games and apps

KB5124010 can break older software that uses AC-3 audio decoding, and Microsoft has not given a fix date yet.

Microsoft says its September 2026 Windows 11 preview update, KB5124010, can make some apps and games crash when they rely on AC-3 (Dolby Digital) audio decoding. The issue is tied to cases where programs fail to start, exit unexpectedly, or break only when specific features such as music playback are used, and Microsoft says the affected software is often older software using Windows’ built-in audio path. The update is optional for many PCs, but it can install automatically on Windows 11 24H2 devices that have the “Get the latest updates as soon as they’re available” setting enabled. Microsoft has not given a fix date yet, but says it is working on one and will update the Windows release health dashboard when it has more information.