Continuous sampling rate lower than 76Hz not possible with NI 9775?

Hi,

I am working with a cDAQ 9171 chassis and a NI 9775 DAQ.

I want to perform continuous data acquisition with a sampling rate of 25Hz. However, I get an error message displaying that the minimum sample clock rate is 76.2939 Hz. 

Is it not possible to sample continuously below this rate? 

Here is the error message:

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Requested value is not a supported value for this property. The property value may be invalid because it conflicts with another property.

Property: NationalInstruments.DAQmx.Timing.SampleClockRate

Requested Value: 25.0

Maximum Value: 20.0e6

Minimum Value: 76.2939

Task name: _unnamedTask<1>

Status code: -200077

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Thanks in advance for your help!