AFE7769D: Inquiry about DPD

Part Number: AFE7769D

Tool/software:

We are using AFE7769D and Icana ICASD4450-D2S, ICASD4450-S2D.

When we triggered DPD with dpd model 4044, there is some EVM fluctuation by about 0.5% periodically. I think that's because of feedback signal. 

I'd like to know how to debug and take actions. And are there any other DPD model I can use?