Just got controller new a couple of weeks ago. It worked fine when I started using it to control fermentation temp of a lager but since I started increasing the temp in the fridge for the diacetyl rest it's wigging out on me. It will run for a few minutes, then it shuts power to the fridge and the display starts alternating between "asd" and the temp (57F). It does this for the asd period, then the power comes back on for 1 second, the display shows 55F and then starts alternating between "asd" and 57F again. It will do this 3-5 times before it will mantain power to the fridge for any time at all. It is mantaining a steady temp but obviously is not operating correctly. I have the probe sandwiched between the carboy wall and a piece of foam insulation. I have the differential set at 1 since the probe is measuring the temp of the beer and not the ambient temp. I did have the asd setting at 1 minute but have recently increased it to 7 to decrease wear and tear on the condensor. Anything I could be doing that is causing this abnormal behavior or do I just have a defective unit?