Pretty sure JACK can host an audio server that other devices can output to. Can't say for sure how easy it is or how it works, but a quick search brought up NetJACK and it looks promising.
Edit: Just re-read and realized you were including a Windows PC and Android phone. There might be utilities to make these work with NetJACK but, I have no idea there.
Happy cake day, seems like you might want to ration that cake though...