I get the exact same thing you have, no idea what causes it. until the car gets up to the middle of the temp gauge i hear the knocking when the car is at idle. Sometimes it's cold enough that it doesn't get up to that temp on my whole 20 minute drive home and at every stop light I can hear it.

That second video sounds a lot like mine.

Mine sounds like the 2nd clip when the engine is still warming up.

Yes thats the exact same noise, Im glad I'm not the only one.
Any idea as to what is causing the knocking?

Push the clutch in to see if it goes away.

I tired it, the sound the goes away every time I push the clutch in

I'll have to try that next time to see if it's the same for me. If so, what does that mean?

Sent from my Galaxy S4 using Tapatalk Pro

Possibly that the small amount of load from the transmission shaft in Neutral causes/contributes to the sound

I have an automatic and I have the noise. I will try and put it in neutral next time I hear it.

It was once speculated that it's the flywheel that makes this noise. It should go away after you drive for a while and the car is fully warmed up. It goes away for me at least.

Maybe this noise is the fuel pump? Since the fuel pump does the "chirping" maybe it does this too haha.

But only thing related to this that I've noticed is when starting sometimes for a few seconds the engine is kinda shuttering/jittering and seems to kinda cut out. Almost like it's running on 3 cylinders. But it only lasts a few seconds till it warms up slightly.

I have it also, usually when the temp is around the 40's. It goes away when I push in the clutch, so it has to be related to the transmission. Let us know what the dealer says

I had this problem last winter,did not notice it until I added the exhaust. Almost like a cold backfire pop. It would do it a few times until the idle became stable.It did not help when I had a lot of load on the engine during idle either.eg (defrost frt and rear/radio running lights) make sure any electric accessory is off when you first start it.

I'm almost at 22,000 miles and have heard my car make this same noise since late November.