I am running KC705/No-OS drivers and I have verified that the A/D path works fine and the D/A path works fine from the FPGA perspective. I can sample A/D Data and FFT looks good for various tones that I generate and on the DAC side, I use the DDS supplied with the reference design and the output on the SpecAn looks good. My goal is to eventually use the A/D data, process it, and send it out to the DAC. My first step, however, is to show that I can pass the signal through directly from the A/D to the DAC. Unfortunately, I have been unsuccessful and I see lots of spurs that depend on input frequency. One thing that happened is the SED functionality was wiped out when I removed the DDS from the DAC logic. How important is the SED functionality? Are there any other "gotchas" i should be aware of?