"For the highest video quality, the camera can also output uncompressed 8-bit Full HD video during recording through the HDMI port. This enables you to use an outboard recorder to capture footage for rich detail and image fidelity."
Seems the D600 doesn't have full manual in movie mode. I'm sure like when the 5D came out with the same problem that it will be fixed with a software upgrade but that is really a dumb move on Nikon to release that.