iPad RTMFP multicast connection issue?

So when I connect to an RTMFP group multicast stream between an iPad and a PC the multicast streams do not send data.

However when I introduce an iPhone to the mix it works perfectly fine. Then when I remove the iPhone the streams between them stop broadcasting. I don't believe they close(). I think the data just stops transmitting.

Its almost as if my phone is acting like a bridge between the devices?

Does anyone know what is causing this? Bug? Network environment?