Constant disk activity on MyBook

I’m wondering if anybody has experienced this, or has any comments/suggestions.

I recently purchased a 1.5 TB MyBook Home external HD to use for TimeMachine.

I migrated TimeMachine to the new 1.5 TB from my ‘old’ 1 TB MyBook Essential using the Disk Utility.

Both the new drive and the old were reformatted as HFS+.

The 1 TB MyBook was nice an quiet, and only made subtle noise when TimeMachine was doing its thing.

The new 1.5 TB is noisy as hell. It sounds like there is CONSTANT disk activity when there shouldn’t be any.  Any idea what’s going on. If this is the ‘normal’ noise level for this drive, then I don’t think I want to keep it.

TimeMachine is configured to run only once per day (in cron), so there should be no activity outside of that time (with the exception of the occasional time when I launch Finder…).

-Dre

I have exactly the same issue on my MyBook 2TB but on a Windows Vista PC. I use the drive with TrueCrypt, so it is entirely encrypted, could this have an effect?

This constant activity sometimes used to stop, but since I copied a lot of data to the disk lately, it seems to not stop anymore. Even if I unmount the device (and of course unmount the crypted volume) it is still ticking. The blue light does not blink, so I guess it is not acutally being accessed from the PC but rather does some kind of internal task.

I ran the Quick Test of WD’s LifeGuard tool and it didn’t show any problems. Also the SMART status seems to be all fine.