Sayyiduna Samurah (may Allah be pleased with him) said: "I have preserved from the Messenger of Allah (peace and blessings be upon him) that he (peace and blessings be upon him) would make one pause (of silence) (in the prayer) when saying the takbir, and one pause when finishing the recitation of the surah." Sayyiduna Imran bin Husayn (may Allah be pleased with him) found fault with him over this, so the people wrote to Sayyiduna Ubayy bin Ka'b (may Allah be pleased with him) about it, and Ubayy (may Allah be pleased with him) wrote back: Samurah has spoken the truth. And he would say: Indeed, Samurah has preserved this hadith from the Messenger of Allah (peace and blessings be upon him).
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6845