windows 8.1

I am having terrible connections with a windows 8.1 laptop. It worked fine for a while and now all of a sudden...major problems. I have checked everything possible. Updated my add-ins, ran the test check and everything is fine. When I launch a class to teach, it is horrible connections and the screen freezes, as well as the video and audio. What is the problem, because it's not just me. I see others asking the same question and I don't see a response from any one.