There are many sources online mentioning the story of how the Alshich once gave a Drasha and the Arizal was present. In the Drasha he elaborated on the 100 different ways Lavan deceived Yaakov. At one point the Arizal started laughing. Later he explained that Lavan had been listening to the Drasha, tacitly admitting to each accusation, but had protested one of the Alshich's accusations. The Arizal said that Lavan was, in fact guilty, however he still had a bit of shame left.
Does anyone know of the original source of this story?