How to eliminate feedback in Sigma DSP ADAU1452

HI everyone

I have the same problem with https://ez.analog.com/dsp/sigmadsp/f/q-a/64300/how-to-eliminate-feedback-in-adau1701/193164#193164..But our DSP is ADAU1452.There are some tool and function.ADAU1452 don't have.

I am using directional microphone and speaker to achieve a simple aduio function,but I have a problem is microphone receive the sound from speaker.it will produce a whistle kind of sound.

I have try NLMS fillter to sovle,but its result isn't obvious.

Please help me

to resolve this problem.

thank you.