Vayne ult is broken

Anyone else experiencing a bug where vayne is in her ult and stealthed, but when she goes to auto attack you she does not reveal herself till after you've already been hit? with enough attack speed it allows her to essentially get two auto attacks in before you can even see her. It's very frustrating and other players in game agreed upon seeing her attack without revealing herself. If found that this is true she should honestly be disabled till it's fixed.