• Success Criterion 1.2.3
  • Conformance level A

Audio Description Track With No Way to Turn It On

1.2.3 — Audio Description or Media Alternative (Prerecorded)

Scenario

Setting

A language-learning app's lesson screen

What’s wrong

audio description track exists but the player provides no way to select it.

Example 

<video src="/lessons/culture-video-with-ad.mp4" controls></video>
<!-- File contains a second audio stream with description, but the
     custom player never exposes an audio track picker -->

Why it matters

A blind language learner has an audio-described version sitting inside the very file they're playing, but no button anywhere lets them switch to it.

How to test

Check the player controls for an audio-description toggle: if it exists but doesn't actually switch on a described audio track, it fails.

How to fix

An embedded description track is worthless without a visible, functioning control that lets viewers turn it on.

<video src="/lessons/culture-video-with-ad.mp4" controls id="lesson-video"></video>
<button type="button" onclick="selectAudioTrack('lesson-video', 'description')">
  Turn on audio description
</button>

Outcome

A blind learner taps the audio-description button and follows the cultural gestures shown in the video.

Who is affected

Blind and low-vision learners can't access the audio description track at all, even though it technically exists in the media file.

Learn more

Related scenarios