ADAU1787: I2S Full Duplex + AEC

Hello,
We have developed a product USB Speaker in our custom use case & the product works well except AEC not being present in our Current Codec WM8904.

Hence we would like to migrate it to ADAU1787. 

We are new to the Analog device & found very few resources in the ADAU1787 chip to implement in our use case.

To eliminate any errors from our custom PCB for this codec migration we would like to use all Demoboard until we can ensure the development phase has been completed.
the hardware connections are shown in the picture below: 

We want to achieve the following to assure the dev phase goes smoothly:
1) I2S IN to DAC OUT. (Eg. music playback)
2) ADC IN to I2S OUT. (Eg. voice memo recording)
3) Full Duplex of DAC & ADC via I2S (a GSM call with a phone via USB C cable.)
4) Implementing AEC.

we have managed to create some schematics in Sigma studio & able to produce some sound on DAC (in the above Step 1 goal) but with more noise than Audio.

Technical details of MCU I2S: 24 bit format all 48kHz

I've attached our Sigma studio Project & please let us know the possibilities.

P.S. Our MCU with our Previous Codec works perfectly with its original software. we are hence using this as a benchmark. 

I've Tried to create a technical support case but it's showing me the following error always.

Thanks for your support.
Gokulnath A R

ADAU1787_I2S_IN_OUT_48K.rar