How to combine audio streams in realtime mode on a node?

Question

Node.js

I'm trying to create something like "internet radio".
Users should receive 1 stream, and the server on the node should merge the streams from the array.
The array can contain, for example, 1) a stream from an audio file (music), 2) a stream from a microphone, 3) a stream from another file (for example, an applause effect). And at any time, any of the streams can be deleted (interrupt the music) or another one can be added (stream from the micro 2nd interlocutor).

Found a lot of examples but they all mostly use ffmpeg and work only with files which in this task will give extreme latency + extra disk IO. Or can write this service in some other language where it is easier to implement?