If I create a digital sine wave generator in the DSP (0 dBFS peak), and measure at the output with MX5G3 at 0 dB and LOUTVOL at 0 dB, I get 97 dB(A) dynamic range turning the generator on and off, while the datasheet says 101 dB(A). If I raise MX5G3 to +6 dB, and LOUTVOL to +2 dB (right before clipping), I get 101 dB(A) dynamic range. Are these the conditions you measured at? Should I leave it at these gains for production to get the best noise floor, or will it vary significantly from unit to unit?
When the button says "Line Out", does that mean "currently in Line Out mode" or does it mean "press to switch to Line Out mode"?