Why is there no sound after the call is answered (Windows, Freeswitch, SIP.JS)?

Windows. Freeswitch Server (IP public).
Set up on the website "Click to Call" using SIPJS (wss-binding).
Subscriber "A" to the website clicks on the button and generates a call to Subscriber "B".
"B" meets and nobody listens to anybody (Neither "A" nor "B"). The recorded conversation captures both subscribers (data are means).
Then what is the problem? The browser or on the server?
July 9th 19 at 11:16

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