Here at 3:00 this person is trying to communicate with someone who has a blank look on their face. What are you pointing at? How many points are you pointing out. Too much information can be blinding. If the chat has been going for 2 hours how much will be remembered? Or, is it that the primary speaker was venting the content of their thought queue. The "blank look" people will likely be multitasking while they emulate participation in the sesson. The presenter will have to cope with the ebb and flow of attentiveness while they grow content from their thought and worry purge. -Know that this has to be helpful, otherwise it would not continue as it has.
Facing you: Are you repeating yourself? You will be repeating yourself until your point is understood. The issue is for you alone, for now.
Facing away: Enough detail will eventually be shared and you and everyone else will understand. React when the point is clear, otherwise wait.
Kevin is here to help if you need a second intuitive opinion.