What the standard says
An alternative for time-based media or audio description of the prerecorded video content is provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such.
Why it matters
A blind user hears the soundtrack. If the price only appears on screen, they never learn it.
What a failure looks like
- failsA tutorial where the narrator says "click here" and the target is only visible.
- failsOn-screen text — prices, error states, code — never spoken.
How to fix it
- doWrite the script so the narration says what the screen shows. This is cheaper than adding a description track later.
- doWhere that is not possible, add an audio-description track or a full text alternative.
How A11ySignal checks it
manual
No automated rule can judge this criterion, and we will not pretend otherwise. A clean scan does not mean 1.2.3 passes — it means nothing we can measure fails. This one needs a person.
What a tool cannot tell you
Whether the audio conveys everything the video does is a human call.