Description: Microsoft confirmed that some Windows 11 apps crashed when decoding AC-3 (Dolby Digital) audio after KB5124010. Find out which versions were affected, why playback could trigger a crash, and how to check the October 13 fix, KB5127648.
If a game or media player began closing unexpectedly after the September 22, 2026 KB5124010 update, Windows' handling of AC-3 (Dolby Digital) audio may explain it. Microsoft confirmed the issue on Windows 11 24H2, 25H2 and 26H2 and marked it resolved by KB5127648, released October 13. The first useful check is your Windows update history, not a reinstall of the game.[1][2]
Why does an audio issue close the whole app?
An affected program may crash on launch or run normally until it tries to play music or other audio. Microsoft lists games, media players and some productivity software as possible examples. The common factor is reliance on Windows' built-in AC-3 decoding. Older applications are more likely to use that component; many newer ones decode audio themselves. This explains why one game might crash while another works perfectly on the same PC.[1]
Check the update and reproduce safely
- Press
Win + R, typewinver, and note whether Windows 11 reports 24H2, 25H2 or 26H2. - Open Settings → Windows Update → Update history. Look for KB5124010 and the fixing update KB5127648. The October update corresponds to builds 26100.9711, 26200.9711 and 26300.9711, respectively.[2]
- Write down the app name and what you were doing when it closed. Save your work before installing updates or restarting.
- Install the latest applicable security update through Windows Update. After restarting, repeat the same action once to check whether the symptom has gone.
| Result | What to do next |
|---|---|
| Only an older game crashes when sound starts | Check KB5127648 first; this matches the reported pattern. |
| KB5127648 is missing | Install the available supported update normally. |
| The app still crashes after the fix | Check the app's own updates and error messages; another cause may be involved. |
| A work-managed PC controls updates | Give the version, KB number and reproduction steps to IT. |
Should you reinstall the app or remove drivers?
Start with the official Windows fix. Microsoft describes a Windows audio-decoding issue, not corrupted save files. Uninstalling a game can remove locally stored data, and resetting Windows is a disproportionate first response. Avoid random codec downloads or forced driver removal. If the problem persists on an updated PC, contact the app developer with the exact steps and Windows build.[1][2][3]
Bottom line
KB5127648 fixes the Windows AC-3 app-crash issue introduced with KB5124010. Check the update before changing game files or sound drivers. A crash that happens when music starts does not mean your saved game needs to disappear with it.
Sources, checked 2026-10-17: [1] Microsoft, Windows 11 release health: https://learn.microsoft.com/en-us/windows/release-health/status-windows-11-26h2 [2] Microsoft, KB5127648 release notes: https://support.microsoft.com/en-us/servicing/os/windows-11/2026/10/kb5127648-windows-11-24h2-25h2-26h2-security-update [3] Microsoft, Windows Update FAQ: https://support.microsoft.com/en-au/windows/deployment/updates-lifecycle/windows-update-faq
