I am driving an AD723 with the output of a triple RGB DAC which is being driven by the digital RGB outputs of an LCD display driver. When I ramp the R, G and B outputs with test patterns, I see those colors go from dark to bright as expected. However, when I set all three to a fixed output I only see grey scale and there is no color, even though I see the voltages that should produce color at the R,G,B inputs of the AD723. I also see no color modulation on the CV output which says the problem is not with my monitor. For example, I can program a high 'Red' voltage and will see at the R input a signal that goes close to 1 volt and then blanks to .35 volts with the other two inputs (G,B) staying fixed at .35 volts. Why would I not see color in this situation?