It is narrated from Sayyiduna Jabir bin Samurah (may Allah be pleased with them both) that Umar bin al-Khattab (may Allah be pleased with him) said to Sa'd bin Abi Waqqas (may Allah be pleased with him): The people of Kufah have complained about you in everything, even about the prayer.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 2481