What does your engine sound like at idle (2017 Accord Touring 3.5L v6)?

[A1218]

The engine produces a light clatter noise at idle. Is that normal?

The Accord has a little over 29,000 miles only.

It's probably been like that since new from what I can remember. Maintenance is done in a timely manner and I’ve kept up with everything so far. All maintenance I do myself.

I have drained and filled the transmission so far, done oil and filter every time the MM comes on (Mobil 1 fully synthetic or Castrol Edge Fully synthetic), changed the engine air filter, cabin filter, and flushed brake fluid followed by bleeding. Everything was bought from Honda besides the oil. 

Anyone experience this? I’ve read an article online about excessive clearance from rocker shaft bridge that needs to be loosened and re-torqued? But like I have said it has been like that since new and I have heard it on another 2015 Accord v6. 

Any ideas? No performance issues whatsoever and it is not related to engine RPMs at idle in the park as I can rev it up all I want with nothing heard at all until it drops back to idling. You start hearing it once it's warmed up only as well. With the gear in drive, the noise goes away and is not heard while driving either. 
 

I cannot pinpoint an exact spot where the noise really comes from and the engine idles smooth as well. Cannot feel any odd sensations when putting my hand on it and when putting my ear close to the engine it doesn't even seem like the noise originates internally as well. 

I attached a clip that I uploaded to YouTube.