When the Imam is reciting, then listen attentively Sunan Ibn Majah 849

Arabic hadith text
حَدَّثَنَا جَمِيلُ بْنُ الْحَسَنِ، حَدَّثَنَا عَبْدُ الأَعْلَى، حَدَّثَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنِ ابْنِ أُكَيْمَةَ، عَنْ أَبِي هُرَيْرَةَ، قَالَ صَلَّى بِنَا رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ فَذَكَرَ نَحْوَهُ وَزَادَ فِيهِ قَالَ فَسَكَتُوا بَعْدُ فِيمَا جَهَرَ فِيهِ الإِمَامُ
Translation
It wasnarrated that Abu Hurairah said

“The Messenger of Allah (ﷺ)ledus in prayer,” and he mentioned a similar report, and added to it,and he said: “And after that they were quiet in the prayers inwhichthe Imam recites aloud.”