Audio file - only playing when play button is selected / clicked

I am having trouble with an audio file automatically starting up when a user returns to a page.

On their initial visit the user needs to click the 'Play' button for the audio to begin and it is working well. I have also set (x2) triggers on the 'Back' and 'Submit' buttons for the audio to stop playing when clicked - this is working fine too. The issue is that when a user plays the audio then goes 'Back' to the previous page... and then returns to the page with audio, the audio starts automatically.

This is not the case when a user clicks Submit and proceeds to the next page and then goes Back to the 'audio page' -then it only starts when the user click 'Play'

In short .... I would like the audio to only ever start when the user clicks the onscreen 'Play' button anytime/anyway they get to the page.