the method is as follows:

operating equipment: OPPO Reno5

equipment system: ColorOS 11.1

program: Tik Tok 2.

1. open the main interface of vibrato short video and click the "publish" button at the bottom.

2. Tik Tok's shooting page will pop up, and just click the shooting button.

3. after the video shooting is finished, click the icon of "select soundtrack" in the upper right corner.

4. Next, in the opened soundtrack page, click the "Volume" tab in the lower right corner.

5. Then, in the settings page that opens, drag the slider of the soundtrack, and you can easily adjust the volume of the soundtrack.