Musnad Ahmad 30:2048

Mu'awiyah ibn 'Amr narrated to us, he said: Za'idah narrated to us, Sulayman al-A'mash narrated to us, from Abu Salih, from Abu Hurayrah, from the Prophet, peace and blessings of Allah be upon him, who said: "When the Shaytan hears the caller calling to the prayer, he turns away, having a flatulence, so that he does not hear the sound. When he finishes, he returns and whispers. Then, when the iqamah begins, he does the same thing."