Audio control

WCAG 2.2 success criterion 1.4.2 is unusually blunt for a Level A rule. If any audio plays automatically for more than three seconds, either it stops itself within those three seconds or the page provides a way to pause it, stop it, or turn its volume down independently of the system volume. That is the whole requirement, and the reason it exists is a mechanical one rather than a matter of taste: a screen reader speaks through the same speakers your autoplaying video is using, so unexpected sound does not merely annoy that reader, it hides the interface from them.

Follow the loop that creates. The audio starts. The voice the reader navigates by is now competing with it. To find the mute button they have to hear the voice announce it, and they cannot, so the only reliable escape is to leave the page or to turn off the system volume, which turns off their screen reader as well. This is why “independently of the system volume” is in the text of the criterion: a mute control that only works by silencing the whole machine is not a fix, and it is why the rule says nothing about how loud the audio is. Speech and music in the same range are still speech and music in the same range.

Three details decide whether an implementation actually passes. The control has to be near the start of the page in reading and tab order, because a stop button after the article is a stop button the reader reaches by listening to the article they cannot hear. It has to have a real accessible name, since an unlabelled icon in a noisy page is unfindable. And the three seconds are measured from when the sound starts, not from when the page finishes loading, so a carousel that begins a video on its second slide is inside the same rule.

The safe design is the boring one: sound off by default, and let the reader start it. That covers the criterion, and it also covers muted autoplay with captions, which is what most feeds have converged on for reasons that have nothing to do with accessibility. Where the sound genuinely is the content, as in a media player the reader opened on purpose, this criterion does not apply at all: the reader asked for it, and what they need instead is a reachable pause and a volume they can find.