Musnad Ahmad 5:102

Khalaf narrated to us, Khalid narrated to us, from Mutarrif, from Abu Ishaq, from al-Harith, from Ali: "The Messenger of Allah (peace and blessings of Allah be upon him) forbade a man from raising his voice in recitation before the Isha prayer and after it, so that he does not confuse his companions while they are praying."