Next button Click sound not working

I have built a course with narration on almost every slide.  As part of the final review, my client has asked if the Next button can make a clicking noise when you click it.  Seems simple enough.  Here is what I did:

Insert the sound file onto the slide.

Create a trigger:  Play media [sound file] when the user clicks the Next button.

Very simple and straightforward...but it does not work and I cannot figure out why.  here is a screenshot of my really simple triggers.

Now why would this not work?  There is other narration on the slides, but why would that effect this?  

Any ideas would be greatly appreciated as this file is due today and this is all I have left to do on it!  

Jill