Audio script file not playing

Hi there, 

I'm wondering if there is a way to trigger an audio file to play on a slide, other than the standard "Play Media" trigger.  We've had a course build professionally a few years ago and yesterday, I made a slight edit to the audio file on one of the slides, re-uploaded the audio to the slide and now it's not playing when I preview the slide.  There are many variables in the project, but I can't see one that would obviously trigger the audio to commence.  (I'm no expert on variables though!!)  I've looked through the other slides with an audio component in the project to see if I can find it, but it has me baffled!  I've attached the file - it's a copy of the original.  The slide in question is 2.7 "Your responsibilities."  Any assistance, greatly appreciated. Many thanks!