--> SIPC freaks out on the receiving side. Probably because
the codec switched from g.711u to gsm inside the rtp stream?
codec changes. But receiving audio still freezes on SIPC if
AVTransmitter.start() is called.
Here we go, i used X-Pro for testing and that was the main problem.
SIPC<>X-Pro fails almost everytime
SIPC<>SIPC fails sometimes
SIPC<>Astersik<>ISDN fails often
SIPC<>X-Lite seems to be fine