Problem:i cannot get the right data from the ADIS16448 when it is waggled

Hi everyone，

     I'm using STM32F103 read ADIS16448(SPI interface). I can get the right data when it is flat on the table (ZACLL_OUT for example, it is close to -1g, the others are close to 0), but the data are same during a period of time(such as 2s), then have a small fluctuation near -1g during anthor period of time. But when i waggle the device, the output of ADIS16448 cannot reflect the real value.

     ADIS16448 was tied to the ankle, when i was walking ,the output of XACLL_OUT is showed in the first pic, the output of XGYRO_OUT is showed in another.

Strange : the same PCB board and  almost the same executive routine, ADIS16334 and ADIS16405 are ok, ADIS16448 isn't.

     I'm looking forward to your help.Thanks.