Assuming, you know how to enter Yostream studio, click the Brand icon located at the bottom-right corner of your screen.
Of the four options, click Audios.
Click the '+' button to add your music file.
Note: Music integration into your live stream is available exclusively to users subscribed to Yostream's premium plan. This feature is not accessible to those on the free plan. Please review Yostream's Pricing Plans to select the option that best aligns with your streaming objectives.
Upload your audio file with the recommended file types. Please note the file size shouldn't exceed 30MB.
The uploaded file will appear below the Volume option. Select it to Play while you stream. Hover your pointer on the file to Pause/Stop the music easily.
You can also adjust the volume by sliding along the control bar.