How does the win10 system solve the problem that the headphones have sound but no sound?

Win10 system how to solve the problem that the headphones have sound but no sound? I searched Baidu for many methods but none of them solved my problem. The following method is very simple, I hope I can help you.

1. Enter SmartAudio in the search box at the bottom left corner of the desktop, and then click on the SmartAudio desktop app under Best Match, which is the speaker.

2, then, open the lower left corner of the "Audio Director", we will see that there is sound outside the computer (sound waves from the computer), and the headphones are not Connected, just plug the headset into the computer, then click the two buttons in the upper right corner of the image below, red or blue, and then you can hear the sound with the headphones.

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