كتاب الأذان
Read the English translation first, with the original Arabic directly underneath.
It was narrated from Khubaib bin 'Abdur-Rahman that his paternal aunt Unaisah said:
"The Messenger of Allah (ﷺ) said: 'When Ibn Umm Maktum calls the Adhan, eat and drink, and when Bilal calls the Adhan, do not eat nor drink."
إِذَا أَذَّنَ ابْنُ أُمِّ مَكْتُومٍ فَكُلُوا وَاشْرَبُوا وَإِذَا أَذَّنَ بِلاَلٌ فَلاَ تَأْكُلُوا وَلاَ تَشْرَبُوا