1.4.2 Audio control
Make it easier for users to see and hear content including separating foreground from background.

About

Individuals who use screen reading software can find the Audio that plays automatically on a webpage or the audio that plays at the same time very distracting and hard to hear.

Therefore, ensure that user has the ability to turn off the background sound, or there is no background audio unless specifically selected by a user.

Example:

Before Rectification

video image without sound control.

After Rectification

video image with sound control.