DAC38RF89: DAC output is abnormal

Hi Team,

The customer use a self-study board to develop LMFs=8212 for DAC38RF89 with the following configuration: 

The JESD204B design on the FPGA side is as follows: 

When DDS-IP on the FPGA side is enabled to send to the DAC, the DACA and DACB outputs of the DAC38RF89 have the following results on an oscilloscope, where the DACB output is abnormal, superimposing high-frequency components. But the overall frequency is controlled with DDS. 

And please see the config file: https://e2echina.ti.com/cfs-file/__key/communityserver-discussions-components-files/119/LMFS_5F00_8212.cfg

Could you help check this case? Thanks.