Thank you for the answer.
I’ve just tested it with no success 
I have modified RFBee.ino to set
Serial.begin(57600);
I also use 57600 in my sample on my Uno.
Opening the /dev/tty.usbserial-A1017ICY with screen at 57600 gives me unprintable chars.
But i can see the right number of “???” every second but not the “Uno” string
Am I missing something?
Have you ever tested RFBee@57600?
Thanks