Microsoft: September updates break audio on some Windows PCs

September 14, 2026 · BleepingComputer · Severity: MEDIUM

Microsoft's September 2026 cumulative updates are breaking audio functionality on some Windows PCs, causing sound output to fail after applying the latest patches. Microsoft has acknowledged the issue and is investigating a fix for affected users.

Key Takeaways

Microsoft's September 2026 cumulative updates are breaking audio functionality on some Windows PCs, causing complete sound output failure on affected systems after applying the latest cumulative update packages.
The audio issues appear to affect specific hardware configurations and audio driver combinations, with Microsoft acknowledging the compatibility problem and actively investigating a resolution for impacted users.
Users experiencing audio problems after the September updates should check Windows Update for driver rollback options while waiting for Microsoft's official fix to resolve the cumulative update compatibility issue.