exFAT drive can't be ejected

I have an exFAT formatted usb drive and I regularly can't eject it on my windows 7 (x64 Pro) machine. It tells me that it is being used by some other process. I've shut all my programs and I've searched for active handles:

> handle.exe L:

Handle v4.0
Copyright (C) 1997-2014 Mark Russinovich
Sysinteals - www.sysinteals.com

No matching handles found.

If I try chkdsk it tells me there's nothing wrong:

> chkdsk.exe L: /F
The type of the file system is exFAT.
Volume Serial Number is C0EF-CF09
Windows is verifying files and folders...
Volume label is seagate2TB.
File and folder verification is complete.
Windows has checked the file system and found no problems.

1953366016 KB total disk space.
1892578816 KB in 451429 files.
    161280 KB in 231 indexes.
         0 KB in bad sectors.
      1024 KB in use by the system.
  60624896 KB available on disk.

    524288 bytes in each allocation unit.
   3815168 total allocation units on disk.
    118408 allocation units available on disk.

But still I get:

FWIW I regularly mount this drive on my Windows machine and my Mac. The Mac sometimes does the mac version of chkdsk (I can't remember what it's called) when I plug it in.

Any suggestions, apart from what I'm about to do: shut down the machine and then unplug it (there's some important stuff on it, I'm not going to risk just yanking it, and yes it's backed up).

Recent Questions...