Amir, if the 6014 is still hooked up to the AP, could you please measure the analog input (CD or any should be the same) to find out if it does not get digitized only because you selected speakers to "large" with no subwoofer and/or Audyssey off. I suspect Denon/Marantz might have been smart enough to allow stereo mode to still bypass the ADC unless the subwoofer, or Audyssey, or both are used. Just my guess but it sounds logical to me based on your findings.
If its already packed then may be you can do this verification test on the 3700 or 6700?
If its already packed then may be you can do this verification test on the 3700 or 6700?