WebRTC - single stream exchange with multiple peers

I have three partners:

• PeerA
  
  stream local media for other users
• PeerB
  
  takes a stream and is on the same computer as PeerA.
• PeerC
  
  takes a stream and is on another machine.

All peers are the last. The signaling server is working - I can see that all descriptions are sent and received as I expected.

The problem I'm running into is that the event is PeerC

onTrack

fired and I have access to the same stream

(same id

) that it succeeds with PeerB

- but for some reason, the stream never appears in the DOM.

My code is based on this: https://github.com/webrtc/samples/blob/gh-pages/src/content/peerconnection/multiple/js/main.js

What could be causing this?