That makes sense. It's probably less "doing crazy convolution calculations on how sampled ambient noise changes as the helicopter gets close to a pole", and more "rotten wood vibrates slower"
FYI, you've been hellbanned for seemingly 6 years.
Probably the account name triggering a spam filter?
Email hn@ycombinator.com, they may be willing to unban you, so other people can see your posts.