(44) باب فِي الْمُؤَذِّنِ يَنْتَظِرُ الإِمَامَ
Jabir b. Samurah said:
Bilal would call the Adhan, then he used come to wait. When he would see that the prophet (ﷺ) had come out (of his house), he would pronounce the iqama.
Reference: Sunan Abi Dawud 537
In-book reference: Book 2, Hadith 147
English translation: Book 2, Hadith 537