i have just the opposite problem with my adler barbour. food gets frozen solid and i
have to defrost to take anything out.
i have the adler barbour super cold machine with the smaller vertical box. i keep two thermometers in the box - one in the fridge, one on the freezer - to make sure everythings working fine, and it is. my box is pretty well insulated and i keep the thermostat set to max.
assuming your adler barbour is working correctly it's possible that your box is not insulated well enough. you can buy a cheap
fridge thermometer for about five bucks. you might try that to see just what temperature it really is in the box. my experience is that most production boats have poorly insulated boxes.....