Sunan Ibn Majah, Hadith 713 ⓘ
It was narrated that Jabir bin Samurah said: "Bilal did not delay the Adhan from its proper time, but he sometimes delayed the Iqamah a little."
حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، حَدَّثَنَا أَبُو دَاوُدَ، حَدَّثَنَا شَرِيكٌ، عَنْ سِمَاكِ بْنِ حَرْبٍ، عَنْ جَابِرِ بْنِ سَمُرَةَ، قَالَ كَانَ بِلاَلٌ لاَ يُؤَخِّرُ الأَذَانَ عَنِ الْوَقْتِ وَرُبُّمَا أَخَّرَ الإِقَامَةَ شَيْئًا .
also referenced under: Book 3, Hadith 8 (In-Book) & Volume 1, Book 3, Hadith 713 (DarusSalam)