Why is my Hitachi Deskstar singing an odd tune, but not death rattle-type metal?

Question

I've got an old Hitachi Deathstar drive that functions perfectly, but is now singing a weird tune when not being accessed. Like its taken up house music on its free time. If it were doing this while being accessed, I would just replace it, but it is nice and quiet when in use.

For some probably useless trivia purposes, the system is Win 8.1, and the drive is a Hitachi HDT725050VLA360 500gb drive.

The noise that it makes closely resembles the following

Cachunk achunk achunk, uuh uuh. Aaah.

This is repeated until such time as the drive notices I'm listening in, whereupon it stops, embarassed.

More seriously, it starts some time after the last access and repeats until I specifically access the drive (e.g., browse to a subfolder in Explorer) or when the song ends (or perhaps the operating system pokes it; I can't tell).

I have used Sysinternal's Process Monitor to watch disk access, and as the song is playing, I cannot find any process that is doing any IO work on that drive. Process Explorer shows that only Explorer having a handle to any resource on the drive, but killing Explorer doesn't halt the song.

I have also made sure that the drive is NOT being indexed for search, nor is it set up for write caching. I don't have any virus software installed (RANU, no install anything that is hackworthy or untrusted) except for Windows Defender. The song doesn't play while doing a manual scan in WD. The drive is only used for long term local data storage (errything is backed up).

I haven't found anything in the driver or in disk management that could be turned off which had any effect. Again, the only thing that seems to stop the song is browsing the drive or waiting for it to end naturally.

Is there something in Hitachi's hardware that is making this sound? Am I missing anything that I could do that would quiet the drive down? What gives?

Answer 1

It sounds like the drive spinning down then trying to spin up again. This is not unheard of, but should probably be disabled / tuned if you know how to. Have a look at http://www.tomshardware.com/forum/245314-32-hard-drive-spinning and see if that helps.