On September 10, Microsoft shipped Patch Tuesday updates for all supported versions of Windows 10, including the May 2019 Update (version 1903). The update comes with a number of security fixes and quality improvements, but it also breaks Windows Search and even audio on some PCs. The last optional update Windows 10 version 1903 had a couple of issues hitting Cortana (SearchUI.exe) to Windows Search. Fortunately, the high CPU has been fixed in the Build 18362.356 (KB4515384). However, some PCs with Windows 10 KB4515384 suffers from an annoying audio bug and as well as a load of other problems. According to numerous posts (1, 2, 3), users are reporting that the cumulative update breaks down audio or reduces the volume when playing games. Tweaking with audio settings and uninstalling the update apparently restores the expected behaviour.

The issue has yet to be acknowledged by Microsoft in its Windows 10 release information page, but users have suggested a few workarounds. In the Windows Sound settings - which you can access by right-clicking the speaker icon in the system tray, then choosing Sound Control Panel from the sidebar options - changing the audio quality to 16-bit, 44,100Hz seems to have fixed the issue for some. For others, enabling and disabling all sound effects fixed the issue.

In related news, Windows 10 Build 18362.356 also breaks the Start menu and Search on the desktop for a number of users. Microsoft says they are investigating the issue and a fix will be included in the upcoming release.