Whiteboard automatically launching during meetings

The last 2 Funerals I have live streamed resulted in an issue. This was where a whiteboard was created without my instigation. In fact on both occasions I was not even in contact with the keyboard of the computer. This is very disconcerting and has never happened in over 100 Funerals. Is this as a result of some bug in a recent upgrade, if so, how do I stop this happening?