´It was narrated from Khubaib bin 'Abdur-Rahman that his paternal aunt Unaisah said:` "The Messenger of Allah (S.A.W) said: 'When Ibn Umm Maktum calls the Adhan, eat and drink, and when Bilal calls the Adhan, do not eat nor drink."
Hadith ReferenceSunan an-Nasa'i / The Book of the Adhan (The Call to Prayer) / Hadith: 641
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:إسناده صحيح