If a descriptive caption or feature would in any way clarify or enhance the viewer's awareness of the audio, it should be indicated.
Consumers prefer that more of such information be included than is often done in current practice.
Background Music Background music should be indicated, especially if it contributes to the plot or mood of the video. A description of the background music should be given wherever possible. Where feasible, a combination of description and onomatopoeia should be used to indicate sound effects. If space or other limitations do not permit the two to be used together, descriptors should be used. Onomatopoeia should not be used alone.