According to the source review from TechRadar Software, Microsoft’s September 2026 optional preview update for Windows 11 has introduced a critical bug impacting gamers and other app users worldwide. The issue involves decoding AC-3 Dolby Digital audio, causing crashes and in some cases serious boot and performance problems without an immediate resolution.
- Bug in September preview update breaks AC-3 audio decoding, crashing games/apps
- Some systems suffer severe boot, performance, and stability issues
- No fix available yet; uninstall patch to recover functionality
Product angle
The source review reports that Microsoft’s September 2026 Windows 11 preview update (KB5124010) contains a bug causing certain applications, especially games and media players that rely on AC-3 (Dolby Digital) audio decoding, to crash or fail to launch. This issue affects users across multiple Windows 11 versions including 24H2, 25H2, and 26H2. While many modern apps do not use this audio decoding method, affected titles and programs encounter instability, severely impacting user experience.
Beyond application crashes, the update has been linked to more serious system problems, such as slow boot and shutdown times, graphical glitches in File Explorer, and in extreme cases, boot failures requiring full OS reinstallation. Microsoft acknowledges the issue but currently has no immediate fix available, advising users to uninstall the preview update to regain system stability. The problem underscores the risks associated with early deployment of preview updates.
Best for / avoid if
This update is best avoided by gamers and users who rely on applications using AC-3 audio decoding, including some media players and specific productivity tools, as they may experience crashes or failures. Those using Windows 11 versions 24H2, 25H2, and 26H2 are potentially at risk, especially if they have opted into receiving preview updates automatically. Users valuing system stability and reliable game performance should hold off on installing this update until Microsoft releases a fix.
Users who have not installed this update or those who do not use affected software can continue normal use without issue, as many modern applications do not depend on the disrupted audio decoding method. Caution is also advised for users who enable early update installations via Windows Insider or automatic preview updates options, given this incident highlights possible instability risks with such updates.
Pricing and alternatives to check
The update in question is a free optional/pre-release patch offered through Microsoft’s Windows Update mechanism. There are no direct pricing implications, but the disruption caused may impose indirect costs related to system downtime or reinstallations. Given the severity of the bugs, many users may consider delaying or skipping this update to avoid trouble. No workaround exists other than uninstalling the preview patch.
Alternatives to encountering this bug currently focus on user choices within Windows 11 update settings such as disabling automatic preview updates or deferring updates until official stable releases arrive. Users might also explore third-party game optimization tools or consider maintaining system restores and backups prior to accepting new updates. Monitoring official Microsoft channels for upcoming patches fixing this problem is recommended.