usb2 drive won't mount using powered hub. But will mount using front / rear ports

Other issues:

The flash drive (contains WAVES Plug-in licenses) will mount if its removed from the hub, then re-inserted back into the hub.

Two (2) Pro Tools iLok dongle's that also use the powered hub are recognized.

I've tried every port on the powered hub. They all function.

Never had this issue using Mac Pro 3,1 Running Lion

Refurbrished Mac Pro 5,1

10.8.5