Hilo with TB card just won't work

I just got my Hilo I ordered yesterday. Today I got a Thunderbolt cable (Apple, 2 m) and wanted to set up the whole thing. At the beginning, I noticed that after making the connection to my computer the device wouldn't show up under the Thunderbolt device list. I installed the driver anyway and was able to get the Hilo to show up in the Device Manager, and the respective outputs also showed up under the Windows Manage Audio section.

However I wasn't able to get any sound through from the computer to the Hilo. If I played the test sound in the output's Properties dialog, Hilo would temporarily show the sample rate being locked for the duration. ASIO driver also had apparently no issues. So there was communication, just no sound, and nothing showing up on the Hilo's meters either. The internal Hilo test sound works just fine though. Strangely when messing around with playback I occasionally got a short buzzing sound.

I then decided to update my chipset's Thunderbolt drivers and then things took an even stranger turn. I now get the LT-TB card showing up under the connected Thunderbolt devices, but even after reinstalling the driver several times, the Hilo won't show up in the device manager or anywhere else in Windows.

And now the strangest thing is that in the "About Hilo" section in the device itself, it now claims that no LSlot is installed where I swear that it had previously shown the LT-TB. I briefly opened up the Hilo and the card seems to sit correctly in the slot, its LED is also consistently glowing green (there is no blinking which I've read occasionally I should be seeing, though)

For all intents and purposes it seems that my unit needs to be serviced, or at least the card does. Pretty frustrating. Any other ideas?