"We were sitting in the mosque with Abu Hurairah when the Mu'adh-dhin called the Adhan. A man got up and walked out of the mosque, and Abu Hurairah followed him with his gaze until he left the mosque. Then Abu Hurairah said: "This man has disobeyed Abul-Qasim.'"
Sunan Ibn Majah Book 3, Hadith 28