Firmware update on DJM-450

When starting Rekordbox while connected Rekordbox urges me to update the firmware on my DJM-450.

So I downloaded the update and followed the instructions to the letter as can be found here: https://www.pioneerdj.com/en/support/software/djm-450/

The DJM-450 does not seem to recognise the usb or the firmware, as it does not show any progress and seems to hang at 0%.

I have tried a couple of different USB drives and formatted them every way possble, starting with the suggested FAT. 

The only thing I can think of is that i'm formatting the drive on a Mac. Could this be the issue? Is anyone else having issues updating firmware on a DJM?