Ichat Freezing..

[yaromaax]

I never really experienced a problem with ichat, i always had outstanding quality. When i go into calls the first second it starts freezing, loosing data and an error message comes up, and laggy, audio is choppy. But never had any of these problems with fios. then i switched to comcast. i believe thats the reason at least. i have try messing with the Bandwidth and already tried changing the port to "404". Nothing works. I video chat constantly. Via skype too. Skype works fine, but i like ichat more and its way nicer, in my opinion. anyways, what do i need to do to fix it. And in conection doctor for Ichat it says it cant regonize my router. Very very confusing for me, and everything is updated..