Cedric gets a closer look at the organ and decides that the organ is not an illusion, but he does not know whether the music was illusionary or not.
Thredra responds to Jack, "In his youth, Count Strahd von Zarovich was a mighty warrior. He thundered across the land like the wrath of a just god. When he grew older, he met the love of his life, Tatyana. Before their love could be consummated in marriage, a curse struck Castle Ravenloft. Everyone in the castle was slain except for the Count. His relatives, retainers, soldiers, and his beloved were all slain. The Count himself was inflicted with undying suffering.
"Ismark and the other villagers have long known that the Count has lived longer than most mortals. They do not know why, however. The Count asks that you do not reveal his secret to the villagers. He does not want to burden them with his tragedy.
"The curse is also why the Count has never asked the Burgomaster of Barovia to tax the villagers to pay for new retainers and repairs for the castle. The Count fears that a restored Castle Ravenloft would suffer again the effect of the horrible curse.
"The count has, however, brought in a small number of retainers from outside the village. Specialists such as myself. We have focused on attempting to determine the nature of the curse and whether there is any cure. One of the specialists created the illusion you saw earlier. We have looked through many ancient texts, but we have not yet found a cure."