resume to saved state on slide to play audio

Hi to all!

I have a slide where there are three characters who take you to three different layers with audio. The base layer also has audio which I want to pause when you go to the other layers.

I've gotten the audio to pause when it leaves the base layer, and play when it leaves the other layers to go back to the base layer. The problem is that the audio, once it plays through, it plays through again if you go back to the base layer. I want the audio on the base layer to play through just once regardless if anything else has been clicked, and not repeat again. I have tried setting everything to resume to saved state, but this did not change anything. Can anyone help?