Wow, it sounds so easy!

OK, you'll have to trust me that it isn't just valve clicking. Oil is OK as well. Also, I don't think it is an engine mount since there are no other symptoms. I would think there would be more shaking than at just that one RPM band (which I've checked again and it is actually around 2,000 to 2,200 RPM)

I retarded the timing and got rid of the pinging (detonation).

So that knocking remains. It knocks more when the engine has a load, like when driving or when the AC kicks in. It sounds like it is coming from a specific location like the 2nd cylinder from the driver's side.

Frankly, if someone else has the same problem and the engine runs well overall maybe it is just me being overly picky. I didn't want to ignore a problem that would come back and bite me some day.

Thanks!