UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:63.0) Gecko/20100101 Firefox/63.0

Steps to reproduce the problem:
I have web application to make audio calls between clients. As server I use FreeSwitch with SIP (using SIP.js) through secure web socket. When I make call between firefox and firefox everything works fine, but when I make call between firefox and chrome I do not hear anything on chrome client. On firefox client I can hear what was send from chrome. 

Using Wireshark I found that stream reach client machine and is correct. After long trial and error I found that creating audio tag in js code and assigning remote stream to it as srcObject helps (adapting solution from WebRTC doesn't work with AudioContext).

What is the expected behavior?
Hearing audio on chrome without setting srcObject in audio element

What went wrong?
No audio without setting srcObject in audio element and without audio element

Did this work before? N/A 

Does this work in other browsers? Yes

Chrome version: 70.0.3538.102  Channel: stable
OS Version: 10.0
Flash Version: 

const audioContext = (window.AudioContext || window.webkitAudioContext || window.mozAudioContext || window.oAudioContext || window.msAudioContext);

var aaaudio = new Audio();                                           <--- adding those lines helps
aaaudio.srcObject = sipSession.mediaHandler.getRemoteStreams()[0];   <--- adding those lines helps

audioContext.createMediaStreamSource(sipSession.mediaHandler.getRemoteStreams()[0])
var gainNode = ctx.createGain();
gainNode.gain.value = .5; 
source.connect(gainNode);
gainNode.connect(ctx.destination);