ADC Readings change between debug / run mode

If I'm stepping through the program (even with no breakpoints), I get  an ADC reading of ~4C3FE, but if I get out of debugging, the number stays at around 4C3FE.  ADC0CON = 8400.

But if I press reset, the numbers change to ~4C60E.  This is with the RTD on the EVAL board, changed to a gain of 1 (trying to get the ADC Example to match my code to match my code in running -- I wasn't expecting this to be hard, but between the diagnostic sources and this "runtime offset", I keep spinning my wheels....

Should the ADC readout change based on running or debugging (though, once initialized under the debugger, the reading doesn't change when the debugger is detatched)?