The latest Patch Tuesday included KB4489899 a new cumulative update for Windows 10 October 2018 Update.
Apart from the above, however, the new cumulative update brought a further problem in Windows. This time, sound performance has been affected by users who have installed more than one audio device.
As Microsoft itself explains, audio applications may stop working after installing KB4489899 cumulative update because the system is set to use a different audio controller than the default.
After installing this update on machines that have multiple audio devices, applications that provide advanced options for internal or external audio output devices may stop working unexpectedly. This issue occurs for users to select an audio output device other than the "Default Audio Device".
In other words, if more than one audio device is installed on your computer, it is likely that the devices, or the audio applications after updating, will stop functioning. Microsoft reports that applications / devices such as Windows Media Player and Realtek HD Audio Manager may be affected.
The way of dealing is the same regardless of the audio player you are using. According to Microsoft, you must select the default audio device you want to use by application. This is only possible through the programs you run, and if your application does not have such settings, there is no way to fix the problem.
For example, in Windows Media Player, you can temporarily fix the error by following the steps below.
You should first select the default audio device you want to use Windows Media Player. If you are using another application, just look for the settings for something similar. Microsoft has the option in the application and you can find it in the path:
Windows Media Player> Tools> Options> Devices
Next, you need to select the device you want to use and click Properties. In the audio playback section, click the drop-down menu and in the Sound Device Select area, select the Default Audio Device.
You can further customize volume settings and many more in Windows 10 from the following path:
Settings> System> Audio> Application volume and device preferences
Of course, you can always solve the problem more easily by simply removing the cumulative update from your device. However, you should do so at your own risk, as this KB4489899 update resolves critical security issues in the operating system.
As for fixing this issue, Microsoft says that if everything goes well we will see the patch at the end of March of 2019.