Speaking of intakes, mine also has been annoying (AEM) but the sound seemed not natural, like something was rattling. It was driving me crazy for a while, I started taping off and ziptying stuff that could have been culprits but the noise would come up at certain speeds and definitely when lifting off throttle, it kinda muddied up the BPV release sound... and I had no idea where it was coming from.
This weekend I plasti-dipped my grill and my little bro's wheels and I decided to take a look at the filter... and found the source of rattles!
See ^ how the filter is in contact with the fender liner? I don't know if there is no one else with an AEM intake and their fender liners rolled flat, but this contact is for sure the source of my rattles.
I didn't have time to try to come up with a fix, I was able to pull on the filter so that it would be offset from the liner, but obviously it wouldn't stay that way. I guess I can try to readjust the hose clamps and clock the whole intake a bit, but seeing how it's mounted to the heat shield, I'm not sure how much I can turn it that way. Any ideas?