"The last instruction that the Messenger of Allah gave to me was that I should not appoint a Mu'adh-dhin who took payment for the Adhan." (sahih)
Sunan Ibn Majah Book 3, Hadith 9
← Previous Hadith "Bilal did not delay the Adhan from its proper time, but he sometimes delayed the Iqamah a little."

Sunan Ibn Majah Book 3, Hadith 8 Next Hadith → "The Messenger of Allah commanded me (with Tathwib) in the Adhan for Fajr, and he forbade me to do so in the Adhan for 'Isha'."

Sunan Ibn Majah Book 3, Hadith 10