I did. Go read it again.

The stock intake system is elaborately and expensively designed with the
very explicit intent of controlling intake noise. If you replace it with an
aftermarket one, the silencing features are gone, so resonance can occur
under certain circumstances and you'll hear strange noises.

You can also check to make sure nothing's loose, and that the intake pipe
itself isn't vibrating in sympathy with the engine. If all is well, you can
only experiment with internal baffling, additional bracing and other tricks
in an attempt to prevent resonance.

Trust me, that "cold air intake' isn't gaining you any usable power that
would not require a dynamometer to see. But it sure *sounds* more powerful,
doesn't it?