I swear the code in macOS that determines HDD spindown time is broken. The setting is supposed to be in minutes, but no matter what I set it to, any attached HDD spins down after 30s.
@siguza i think it's always worked for me on sata drives and never on usb ones. no clue if it matches what you're seeing though
Just for personal use. Please click here if you're looking for my website.