WebRTC configuratoin problems

While trying to set up all necessary components to enable WebRTC, I faced some problems. First of all, I tried to use public ERS on 52.6.14.61 host. I pulled stream from camera to my local EMS instance and named it \”test-steam\”. After that I sent to EMS the following command: 

startWebRTC ersIP=52.6.14.61 ersPort=3535 roomID=test-room

After all this actions, I had both the stream and the room parameters for evowrtcclient. So I went to http://ers.evostream.com:5050/demo/evowrtcclient.html?stream=test-stream&room=test-room to see the video playing but nothing happened. When I checked the browser console, I saw the following error:

GET http://52.6.14.61:3535/socket.io/1/?t=1481165489699 net::ERR_CONNECTION_TIMED_OUT

So it seems that 52.6.14.61 host was not available. That is strange, because when I sent startWebRTC with this host as ersIP parameter I got the SUCCESS response. Also, after I failed to use public ERS I tried to set it up locally. I downloded and installed all necessary components as it was described in manual (NodeJS with NPM, restund, the ERS module itself), disabled tokens in default.json ERS config file and changed the ERS_IP_String to my local instance ERS ip in the evowrtcclient.html that is located on the local EMS instance. Then I repeated the actions that are described above. I only changed ersIP parameter of the startWebRTC command.  After that, I went to http://localhost:8888/demo/evowrtcclient.html?stream=test-stream&room=test-room. This time there were no errors in browser console but stream still was not played. In \”debug messages\” of the evowertcclient \”connection ready\” and \”connection failed\” messages appeared and also there was an error in the EMS console log:

STUN (192.168.44.158:64317) has no valid candidate!

I don\’t know what to do with this problems. Maybe I have done wrong steps while setting up this components? Could you help?