Stable volume
By default, stable volume is turned on when you’re watching videos on YouTube. Stable volume balances the range between quiet and loud, continuously adjusting volume levels to reduce variations in sound.
Notes:
- Stable volume isn’t available for all videos.
- This feature is turned off for YouTube Music and official music videos.
If you don’t want stable volume turned on, you can turn it off while watching a video.
Steps to turn off stable volume
- At the top of the video, tap Settings
.
- Tap Additional settings.
- Turn stable volume on or off.
Turn off stable volume on your TV
- At the bottom of the video, tap Settings
- Uncheck the box for Stable Volume to turn off.
Voice boost
Voice boost makes it easier to hear dialogue by reducing background sounds and highlighting vocals. You can enable the feature when viewing videos on your computer or TV.
Notes:
- Voice boost isn’t available for all videos.
- Stable volume is automatically turned off when voice boost is on. However, both Voice boost and Stable volume balance the range between quiet and loud.
Turn on/off voice boost on your computer
At the bottom of the video, tap Settings 
Turn on/off voice boost on your TV
At the bottom of the video, tap Settings
- Click on Audio.
- Check the Voice boost box.
- Uncheck the box for Voice boost to turn off.