UE4 App no voice when I click other program

Open the UE4 app. When I click on the UE4 app, I will hear sounds. When I click on other programs (such as task manager), the UE4 app will be silent. What configuration I need to do (try adding “-AudioMixer” to the program command line, no effect)

I have find it
https://answers.unrealengine.com/questions/66918/keep-audio-from-losing-focus.html