Your voice is breaking up.
Please try these 4 steps one at a time:
1. Turn off your camera.
2. Turn off your incoming video (click X on any showing video image)
3. Lower your Connection Speed (click File on top left and select Connection Speed ) .
Lower this to [Up to 1 mbps].
4. If all else fails, please click [Audio] from top menu bar and select [Reconnect].
★For Mac users, please click on [File] and select [Reconnect]