The muezzin of the Messenger of Allah ﷺ reported, my father told me from his father, from his grandfather, that the Messenger of Allah ﷺ ordered Bilal to place his fingers in his ears and said, "It will make your voice carry farther."
حدثنا هشام بن عمار قال حدثنا
مؤذن رسول الله ﷺ حدثني أبي عن أبيه عن جده أن رسول الله ﷺ أمر بلالا أن يجعل إصبعيه في أذنيه وقال إنه أرفع لصوتك
No references are available.
Its chain is daif. Busiri said, this is a daif chain due to the weakness of the sons of Saad al-Qarz, Ammar, Saad, and Abdul-Rahman.