Musnad Ahmad 907:196

Yahya ibn Hammad and ‘Affan narrated to us, they said: Abu ‘Awanah narrated to us, from Simak, from Jabir ibn Samurah, who said: "The Messenger of Allah (peace and blessings of Allah be upon him) used to perform the prayers similar to your prayers, but he would delay the ‘Atamah (Isha) prayer slightly after your prayer. And he used to lighten (shorten) the prayer."