DAQ measuring lower voltage than input

Hello,

We are using the following hardware to read voltage input:

1. NI cDAQ  9171

2. NI 92017 with DSUB.

Four channels ( AI1,AI2,AI3, AI4) are connected to voltage source(4-20mVolts).

We read on the input terminals to the NI 9207 Box (using a digital Voltmeter), the voltage is consistent 4.06 mVolts.

However, on the NI - Measurement and Automation Explorer the voltage drops to 3.35 mVolts.

Do we need to correct anything in the setup for the offset in voltage?

Configuration of our setup:

Thank you for your help.

Best Regards,

Abhishek.