Hi Dave
I know you said to drop this but I am curious how you are making the measurements. Are you using HDSDR S meter and spectrum levels to characterize the Ensemble II? If so, these measurements are subject to the S Meter calibration function within HDSDR. Calibration requires an RF signal of known level into the Ensemble and then using the S Meter calibration function to make HDSDR indicate the known level.
Warren Allgyer - WA8TOD