Get sound from system C#

Hi, follow to that formula which is working:

void Start() {
        AudioSource aud = GetComponent<AudioSource>();
        aud.clip = Microphone.Start("Built-in Microphone", true, 10, 44100);
        aud.Play();
    }

I would like to to get system sound (aimp, media player) - everything what i can hear from my speaker but I have no idea how. That scrennshot from Aimp3, maybe it will help.

for that you’ll need to use plugins or write your own, which can communicate with software outside of Unity.

Plugin Manual

@Hexagonius, there is really no other way? If not could you link here some stuff how to get “speakers data” via code or something like that? I cannot find it anywhere or maybe there is plugin for that?