AD5940 : Exitation frequency is different from measured frequency

I am testing EVAL-AD5940BIOZ for 4-wire bio impedance measurements.

There is issue on measurements frequency. The test environment is follow.

A 1kΩ resistor was connected to EVB. Two probes of oscilloscope are connected to each lead of resistor.

Frequency was measured with subtract function of oscilloscope. (The setting was effective in other BIA AFE test.)

A SensorPal GUI was used to configure EVB.

However, measured frequency is different from setting frequency.

For the 200kHz setting cause a 12.5kHz. For the 100kHz setting cause a 6kHz. It looks like frequency is divided in 16.

I also tried to configure EVB with source code, but the result is same. I also tried to trouble shoot refer to 42page of datasheet. 

How can I fix it? Could I get an updated GUI? Or EVB jumper should be adjusted to BIA mode?

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