Sinan bin Abi Sinan narrates from Husayn bin Ali (may Allah be pleased with him) that when the Messenger of Allah (peace and blessings be upon him) hid "smoke" (dukhan) for Ibn Sayyad and asked him what he had hidden, he said: Dukh. He (peace and blessings be upon him) said: "Be gone! You will never go beyond your appointed time of death." When the Messenger of Allah (peace and blessings be upon him) turned away, the people said: What did he (Ibn Sayyad) say? Some said: Dukh, and some said: No, rather Zukh. The Messenger of Allah (peace and blessings be upon him) said: "This is how it is: you are differing even while you are with me; so after me you will differ even more."
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 2896