Been having the same exact problem since yesterday I think. Running Livestream on Google Chrome, Windows 7 Professional, Dell Latitude E6520.v
The chat and chat buttons work fine. The mouse cursor shows up on the gray bar below the video itself and seems to act as though it is hovering over the "Pause" pop-up button, because when you click, it pauses the video. Click again and it unpauses. It's quite difficult to do other things that require sound if I want to keep the livestream up. Any help at all would be greatly appreciated!