That's it, you'll have to trade it in for an auto now
I probably would have got the auto if it was available with the Brembo package in 12.
Went out and drove it and listened again. Now I'm wondering if it may be an exhaust knock. It sure sounds just like the thumping I hear out of my Borla S types at idle when I listen at the tip. I have stuck my head under the car everywhere and it is very smooth and quiet. Inside the car if I listen around the floor boards or put my ear down to the gear shift lever it is very quiet. I just hear it when I am sitting up. Cabin resonance from the Borlas? But that doesn't explain why it seems to go away (actually just lessen) when I push the clutch in, unless that is changing the engine loading just enough to affect the sound a bit. And barely raising the rpms makes it go away completely and not just increase in frequency. It's all rather weird.