Chrome and Safari since then have changed their audio policies. Chrome has the notion of a ‘Media Engagement Index’ which further complicates things, but the key thing is that both Chrome and Safari are waiting for some user action to start the audio. Mobile browsers were the first to restrict audio from playing when initially loading the page, but now most browsers will want to see some click or tap before playing sound.
For your case, the error shown in Chrome is:
The AudioContext was not allowed to start. It must be resumed (or created) after a user gesture on the page. https://goo.gl/7K7WLu