Windows 11 26H2/25H2/24H2: Apps needing AC-3 audio decoding may close unexpectedly
Summary
After the Windows updates of September 22, 2026 (KB5124010) and later, some applications that need to decode AC-3 (Dolby Digital) audio might close unexpectedly. Microsoft has resolved the issue with the updates released October 13, 2026 (KB5127648) and later.
Symptoms
Affected applications can fail to launch or close without warning. Other applications work normally until certain features are used, such as playing music. Affected applications can include games, media players and certain productivity applications.
Affected
- Windows 11, version 26H2 (OS build 26300.9550 with KB5124010)
- Windows 11, version 25H2 (OS build 26200.9550 with KB5124010)
- Windows 11, version 24H2 (OS build 26100.9550 with KB5124010)
- Mainly legacy applications that rely on the built-in Windows audio decoding; many modern applications include their own decoder and are not affected
- Windows Server: not affected
Workaround
No workaround known.
Fix
Resolved by the Windows updates released October 13, 2026 (KB5127648) and later. Microsoft recommends installing the latest security update.
Recommendation
Install the latest cumulative update (KB5127648 or later) on all Windows 11 devices. If older line-of-business or media applications crashed after September 22, 2026, check the update level first and retest after updating.
Reports from the community and trade media
Reports from forums, Q&A sites, Reddit and trade media – linked only, without the names of the authors; the vendor’s statement is authoritative.
- KB5124010 update crashes some games and apps News · bleepingcomputer.com, 19 Oct 2026
- KB5124010 disaster on Windows 11 News · tech.yahoo.com, 5 Oct 2026
- KB5124010 update crashing games and apps News · windowsdigitals.com, 15 Oct 2026
Sources
- Windows release health: Windows 11, Version 26H2 Vendor · learn.microsoft.com
- Windows release health: Windows 11, Version 25H2 Vendor · learn.microsoft.com
- Windows release health: Windows 11, Version 24H2 Vendor · learn.microsoft.com
- KB5124010 Vendor · support.microsoft.com
- KB5127648 Vendor · support.microsoft.com
Compiled from the sources listed and translated with AI (Claude); status and dates come from the vendor. The vendor’s statements are authoritative. Updated 1 Nov 2026, 15:48.
Where the information comes from
We continuously read the vendors’ official sources, community reports and trade media and summarise them in our own words, with a link to the source:
- Microsoft: Windows release health (Windows 10/11, Server 2016 to 2025), Windows message center, known issues of Microsoft 365 Apps (Outlook, Excel, Word, PowerPoint), Edge, Intune, Autopilot, Windows 365 and Entra Connect, Microsoft KB articles with timelines, Exchange and Windows IT Pro blogs, optionally Microsoft 365 service health and message center
- other vendors: Veeam KB, Citrix (known issues), Ubuntu and Debian (regressions), Broadcom (VMware), Fortinet, Cisco, Mozilla, Let’s Encrypt
- community (title, short excerpt and link only, without the names of the authors): Microsoft Q&A, Microsoft Tech Community (discussions), Veeam R&D Forums, Eleven Forum
- targeted web research with AI (Claude), e.g. on the updates of the month – this also finds discussions on Reddit and in forums; such entries are labelled as community reports until the vendor confirms them
- early warning from trade media (title and link only): Born’s Tech and Windows World, BleepingComputer, AskWoody, Windows Latest, Windows Central, gHacks, The Windows Club, Deskmodder, Dr. Windows, WindowsArea, Frankys Web, heise online
Summary and translation with AI (Claude by Anthropic) – without any data of visitors.
Affected? We can help.
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