AD7266 Erratic Readings

I have the AD7266 set up with 12 single ended channels, each reading a voltage output from a different resistor divider.  The lower resistors of the dividers are all connected to ground, with the maximum R being about 4Kohms.  Expected value at each divider is about 2.5V, but I'm reading ~1.4V at each.  The strangeness happens when I read from the ADC and also probe the divider with a multimeter.  Once I probe the voltage with the meter, the ADC readings jump to where they should be.  Note that this only happens on the single channel that I'm probing with the meter, the other 11 channels maintain their inaccurate readings.  When I remove the probe, they go back to being inaccurate.  I'm sampling at 2MSPS (5V AVDD, 32MHz clock) and am stepping through each channel sequentially, one reading per channel.  

All the GND pins on the chip are properly connected and I've verified that my resistor dividers are properly connected.  Any suggestions on where else I need to be looking?  

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    •  Analog Employees 
    on Aug 24, 2018 12:50 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin
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  • 0
    •  Analog Employees 
    on Aug 24, 2018 12:50 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin
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