Incorret ADC read from Xbee3 micropython

i have a strange problem using the Xbee3 embedded micropython and ADC read.
I have the pin D0 configured as ADC with vref set to vcc.
If i read the acd value via transparent mode, i get a good value; if a make a read via micropython, i get a wrong value about 4 time greater than the good value…

I didn’t find any solution… the XBee3 have the last firmware and the problem appear with the pro and also standard version…

Some one have some clue??