Engine rattle, knock?
 

What's up everyone? I've got a '94 CD5 EX 4cyl AT with a little over 206k miles on it. Since I bought it back in December, I've been a little concerned with the slight knocking/ticking/rattling sound coming from the engine. I recorded a video to demonstrate, and I'm not talking about the valve train clatter, nor the exhaust manifold cover rattling. It happens all the time when the engine is at idle, but most notably when it's warmed up. It happens from about 700-1500RPM, and seems to mostly go away, or at least become consumed by the rest of the engine noise. Honestly, in the video, the noise is quite a bit exaggerated as far as the loudness of the knock, compared to what it normally sounds like. Most of the time I have to be in the garage to even notice that the sound is happening.
Between shots of this video, I tried using a mechanic's stethoscope to determine the origin of the sound, and I honestly didn't gain any useful information from what I found. I listened all around the front of the upper and lower block, as well as around the valve cover to no avail. Any input or recommendations would be greatly appreciated.

1994 Accord Engine knocking? - YouTube

so you're saying the noise has always been there since you've owned the vehicle? possible piston slap? what is the service history on the car? i wouldn't worry about it too much.