Course-wide variable for sound on buttons?

Hello there! I love when I hover over an interactive button and it makes a sound - for me , its a polishing step that makes the course feel more like an app. However, I am currently importing the sound into each slide and setting a trigger to play the sound every time a user hovers over a button. Is there a way to set a course-wide variable so that I don't have to do this on every slide? That would save me a ton of time. I've included a demo slide for review. Thank you!