Getting a Hot Swap unit to work!

I have a quick question, I purchased a Hot Swap unit for my computer and this is one of the tray less versions listed on E-Bay for around $12.00 US
It works well sort of, if I install a hard drive and boot with a hard drive in the tray I can view that the hard drive. If I then remove the hard drive and install another hard drive I can also see the new hard drive. The issue is if I boot the computer with NO hard drive installed in the hot swap unit then install a hard while the computer is running my system will not recognize the drive until I reboot again. Is this normal, I have tried the unit with Windows and Linux and it works the same in either operating systems.
Any suggestions, as this is what I had hoped would happen.

Do you have AHCI enabled for the SATA controller?

Thank you for the reply!

Yes AHCI is enabled.

Are your SATA drivers up to date? That's all I can think of. It is possible that your SATA controller or the driver just doesn't support hotswap.

What's the manufacturer and model of the hot swap you bought?

Have you tried all the bays after a full boot?

Check your motherboard manual for hot-swap capability. You may have to flash your bios if they provided functionality in an update.

I have made sure that I have the latest SATA drivers and Bios drivers installed.
The motherboard that I am using is and ASUS Sabertooth 990FX Rev. 2 logic board.
Regarding the Hot Swap tray that I purchased it is just a single tray not rack with multiple trays.
This item was purchased from E-Bay and has no name applied.
Here is a link to the tray:

As a final round up for this discussion I have just received an e-mail from Asus advising that this board does not support Hot Swap!
Very surprised by this as it is a high end board.

If you have any free PCI-e slots you could pick up a SATA card which supports it and use that. Sucks, but it's cheaper than a new motherboard :P

Thank you Dexter that is a great idea!