Web Audio will follow the rules of the autoplay policy already followed by other parts of Chrome able to produce sound. When an AudioContext is created, it will start as suspended if it wasn’t allowed to play. Calling resume() will only start the AudioContext if it is allowed to play. Furthermore, a previously blocked AudioContext will automatically be resumed if start() is called on a connected node after the document is user activated.
Samples: https://mounirlamouri.github.io/sandbox/autoplay/webaudio.html