Unable to hear any Audio in most of my scenes

I’m having a problem where I can’t hear any audio when played from my scene. I have checked that I have an audio listener and an audio source as well as volume checks both on my computer’s mixer and in Unity. When I create a new scene and just quickly throw an audio source and listener into the scene, it suddenly works. I have no idea why this is happening.

Some extra background info: I just recently picked up this project from someone else who got the majority of these mini games in their current working state. I’m not sure if it’s because he created the game using Unity Pro and I’m temporarily using free Unity? The problem is when I try to run it on his laptop I am still having the same problem.

He did start it up with Audio Toolkit as well, and I’m not sure if that’s the problem in some way? I tried bypassing it to no success.

Silly me. The programmer setup a mute button and it was set to off by default.