Mine does it now and again when cold, different engine of course.
Sometimes does it for a few days after topping up the oil or after oil change. Used to make me very paranoid that the engine would go bang, but its usually fine after its up to normal temperature - they seemed take ages to warm up, even in summer. Seems much happier after a couple of hundred miles after new oil.
Tappets on modern engines should be self-adjusting, perhaps mine are as lazy as me!