I have the AD9956 eval board and am feeding in a 1V peak to peak 400MHz ref clock. I am able to generate an output clock at 50Mhz, but its only 400mV peak to peak. The logic bus this runs into operates at 1.8V, and I was expecting this clock to output around there. Any idea what I could be doing wrong? Or is this part intended to output the clock voltage around 400mV peak to peak?