Talking on the phone is not against the ToS, but it is advised to mute the microphone when talking.

That being said, if you are rebroadcasting a radio or Television program this ‘could’ fall under the copyright section of the ToS, therefore breaking the ToS.

BUT if your question is regarding someone hosting a ‘talk show’ on Chaturbate and asking their viewers to phone into the ‘show’ this a grey area.  Chaturbate do state that anyone that appears on cam ‘body or voice’ have got to be verified on that account.. but the grey area is they class this as the other person to be in the same room as the person on cam.