Jami` at-Tirmidhi 311
جامع الترمذي#311Da'ifUbadah bin As-Samit narrated:"Allah's Messenger prayed the Subh prayer, and he had difficulty with the recitation. When turned (after finishing) he said: 'I think that you are reciting behind your Imam?'" He said: "We said: 'Yes, Messenger of Allah, by Allah!' He said: 'Do not do that, except for Umm Al-Kitab, for there is no Salat for one who does not recite it
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirDaif
Al-AlbaniDaif
Zubair Ali ZaiSahih
In-book reference: 2:163