jeff, the Oppo 981 doesn't have any black level enhancement setting to turn off or on; there's just a brightness setting that can be anywhere from -20 to +20, and I've left it at its default of 0.
Using DVE for calibrating the DVD input, the brightness setting on the TV is 53. Using the HDNet test pattern for calibrating the HD PVR input, the brightness setting on the TV is 64. A seemingly big difference, but not necessarily important if I get similar results in picture quality.
The post-calibration picture on the DVD looks incredible, no problem with black levels. But the post-calibration picture on the HD PVR does seem to have a problem with its blacks: even though it's calibrated with the test pattern, the blacks are still a bit lacking. No one here uses the HDNet test pattern to calibrate their TV?
cheers,
supervij