Live audio with Socket.io

I made an application to send live audio with Socket.io. The problem is that it only works between tabs in the same Chrome window. When I try to send or receive audio from another PC or even from another window, this error appears:

GET blob:https://server/ce74cfe7-bb9c-40b0-9cb0-1138b22b1b11 404 (Not Found)

This is the code in main.js (of the page):

$(document).ready(function(){
    var socket = io("https://server:4000", verify=false);
    socket.on('audio stream', function(blob){
        var video = document.querySelector('video');
        video.src = blob;
    });
    $('#ptt').click(function(){
        micOn();
        document.getElementById("ptt").disabled = true;
        document.getElementById("ptt-off").disabled = false;
    });
    $('#ptt-off').click(function(){
        stream.getAudioTracks()[0].stop();
        document.getElementById("ptt").disabled = false;
        document.getElementById("ptt-off").disabled = true;
    });
    function micOn(){
        navigator.getUserMedia = navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia;

        var constraints = {
            audio: true,
            video: false
        };
        var video = document.querySelector('video');

        function successCallback(stream) {
            window.stream = stream; // stream available to console
            var blob = window.URL.createObjectURL(stream);
            socket.emit('audio stream', myName, blob);
        }

        function errorCallback(error) {
            console.log('navigator.getUserMedia error: ', error);
        }

        navigator.getUserMedia(constraints, successCallback, errorCallback);
    }
});

This is the code on the server (index.js):

socket.on('audio stream', function(blob){
    socket.broadcast.emit('audio stream', blob);
});