1998 Dodge Dakota Engine Knock

So I have a low knock that kicks in when I start up the truck. It is pretty low in the level of the knock, but it is also a low tone "soft" knock (for lack of better words).

It is real subtle. So that point being made, after about five seconds the knock kinda fades out and only when I hit the gas does it come back a little.

Is it because the knock sensor kicks in that it goes away?

And if that is the case, either way, is it possible there is an issue with the timing chain causing the knock, or internal issues?