Periodic clunking noise from shucked WD drive?

I have an 8TB WD Elements (purchased in June) that I was using in the original enclosure, but just recently shucked and put in my NK v4.5. I can’t tell if I just started noticing or it just started happening, but there’s a sort of normal-sounding clunking noise periodically (every few seconds) that sort of sounds (to me) like a drive head parking. A few things I’ve checked already:

  • The drive passes the extended test in Lifeguard Diagnostics with flying colors
  • The sound happens at the same interval when I’m just sitting in the BIOS or when the data cable is unplugged altogether
  • Because this happens with no data cable connected, I know it can’t be anything accessing the hard drive (which I also checked in Windows with procmon)
  • Tried disabling APM via CrystalDiskInfo

I’m fairly new to using internal drives of this capacity and type, and the rest of the build is completely inaudible (semi-passive CPU cooler and PSU that almost never turn on), so I’m wondering whether this is a normal hard drive sound and I’m just hearing it 'cause everything else is silent and I’m not used to it.

Thanks in advance!

I haven’t experienced this - what OS are you running? Is drive shutdown turned on or off?

I’m running Windows 10, but it does the same thing with the data cable unplugged, even in the BIOS. As far as I can tell, all power-saving features are disabled. Is there somewhere in particular to check for drive shutdown?