How to adjust music and voice over volume/loudness?

Volume Mixer

• Click on the speaker icon to change the volume.
• The mic icon controls the voiceover volume.
• The video icon controls the volume of the video.
• The music icon controls the volume of the background music.

Auto Ducking

With the auto-ducking option enabled, the Loudness of background music gets automatically lowered when the system detects a voice-over being played simultaneously.  

There are three levels available for Auto Ducking: 

• Low 
• Medium
• High

The blue indicator(Music) corresponds to the Loudness of the music when the voice-over is being played.

The orange corresponds to the Loudness of music when the voice-over isn't playing.