Sorry for the late reply, I don't get around here to often anymore.
I'm on Windows 7 Pro, and use the latest drivers provided by Presonus.
So your saying that the Presonus Control Panel shows the Firepod but Sonar X1 is not showing it in it's "device list"? That would be very odd... I don't know if I have an answer or even a suggestion for that.
If the Firepod was not showing in the Presonus Control Panel then I would suggest it is not syncing. Mine died about 4 months ago (would not sync with the computer) and I had to replace a capacitor in the unit. Been working perfectly ever since (knock on wood).... But when that occurs, the light on the presonus stays red (not blue) and the Presonus Control Panel doesn't show anything in it's "active units" box.
Sorry, wish I could help more.