I've been trying to use the multiplier of AD9910. When running the evaluation software, I check the multiplier enable, set the multiplier to 5x and provide the dds with an input frequency of 100 mhz from a signal generator. My problem is the the dds does not output accurate frequency. I require a 40 mhz output, the dds outputs around 36 mhz. Am I missing something in the multiplier setting? Should there be any hardware changes on the evaluation board to use the multiplier?