Signing verification failure breaks audio functionality in Windows 10 Version 1511

Applies to: Windows 10, version 1511

This article describes an update that fixes an issue that may result in audio playback issues on a certain set of users' computers in Windows 10 Version 1511.


A Conexant Audio Processing Object (APO) fails a signing verification. This causes the system to lose audio functionality.

How to get this update

Windows Update

This update will be downloaded and installed automatically.


There are no prerequisites for installing this update.

Registry information

To apply this update, you do not have to make any changes to the registry.

Restart information

You may be prompted to restart the computer after you apply this update.

Update replacement information

This update doesn't replace a previously released update.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.


Learn about the terminology that Microsoft uses to describe software updates.