Play sound only when the user asks
The simplest answer to autoplay is not to autoplay. G171 says play sound only when the reader asks for it. That removes the problem rather than managing it. It applies to any technology that can play sound, so it is a rule for the pages that do not autoplay yet as much as for the ones that do. This is a sufficient technique for 1.4.2 Audio Control at Level A. W3C's own reasoning names screen reader interference directly, which is unusual. Most technique pages describe a mechanism. This one describes the collision it prevents, and that collision is the reason the rule exists at all.
How we find it in an audit
Our reviewers load every page with the sound on and listen before touching anything. Autoplaying video counts. So do background loops, and so does anything a third-party embed starts on its own. Where sound does start automatically, we move to the mute-control test instead, because at that point the question is no longer whether it plays but whether it can be stopped.
How affected users experience it
A screen reader speaks through the same speakers your jingle uses. When both start at once, the speech becomes unintelligible, and the user cannot mute the page without silencing the tool they navigate with. They are now searching a page they cannot hear for a control they cannot find. Waiting for a Play button avoids all of it.
Passes vs. fails
Passes
<audio controls src="jingle.mp3"></audio> sits silent until the reader presses its Play button.Fails
<audio autoplay src="jingle.mp3"></audio> greets every visitor with music they never asked for.How this gets tested
The W3C publishes test rules that define what a checker looks for here.
- Audio or video element avoids automatically playing audioA tool can check this
- Audio or video element that plays automatically has a control mechanismA tool can check this
- Audio or video element that plays automatically has no audio that lasts more than 3 secondsA tool can check this
Other ways to satisfy this rule
5 guides on this site are filed under 1.4.2 Audio Control. W3C lists this one as sufficient for that rule on its own. Implement it correctly, in a way your readers' software actually supports, and the rule is met.
This guide is our interpretation of W3C technique G171: Playing sounds only on user request. W3C publishes its techniques as guidance rather than as the standard, and says so on every one of them. The success criterion is what conformance is measured against, and a technique is one documented way to meet it.