TelePresence Endpoints can support up to two calls, the first being a video call and second audio only. how i can make both the call  to be video calls

Hi    i have Cisco telepresence MX800 when i make call between telepresence and IP phone the first Phone can make video call but the second one can't make video call just Voice call how i can edit it and allow to second one to make video call.

hi I have 5 phone i need to configure it when i,m pichup the first phone the fourth phone start ringing