How can I set audio to play as if it was into the recording device?

I’m playing a lot of Echo Arena late at night, and my girlfriend is annoyed that I’m talking too much. I want to make a simple program that will detect a button input from Oculus Touch, and then play a pre-recorded soundbyte into the recording device (as if it was being played into my microphone), rather than out of my playback device.

I’m fine with the input part, but I’ve not yet played about with audio in Unity, so I’m looking for some ideas.

Any ideas on this. I have it so it plays the sound when I push A on the Touch controller, and it’s not rendering anything in the headset, so I can see the game.

I just need to work out how to make it play the sound so my friends can hear it rather than me.

Any pointers in the right direction would be appreciated.