Audio working as exe, not as html

I am quite new to Lectora using the latest version. I have audio files associated with each page. I want the audio to autostart only the first the page is visited. I have created a variable to record if the page is visited and an action to play the audio if the page has not been visited. When I preview in Lectora this works fine. When I publish to html the audio does not autostart at all, I have to click the audio button to play. When I publish to exe it works fine. Any ideas?ThanksSheree