I used the circuit same as on the datasheet CS6422. But in my case I did not use any of the control pins (DATA,STROBE,DRDY,RSET) instead I put pull up resistor for RSET (50K from 5VDC). From the very first I connect it to telephone handset while calling. Then I pull down the RSET pin then it was working. I even place the other handset (my caller) very close and no more howling. Acoustic echo was totally removed. After, around 5mins we stop the call. Then call again, I repeat my steps as what I did before but audio theres no audio on the outputside of both path. I scope the inputs, at pin NI theres an audio signal same with APO when i speak to my mic. But on there outputs, NO and AO no audio signal. What is wrong is the ship worn out? Please explain further why I cant have the audio on the outputs.?