I received a 01645DI weather station for Christmas and finally installed it yesterday. It will run flawlessly for between 40-60 minutes and then the base station freezes. The display becomes static, the time does not change nor are any of the readings updated. The buttons are unresponsive. If I press the reset button, everything resets and works properly for for less than an hpur and then it freezes again. I installed it with new lithium batteries in the outside unit and new alkaline batteries in the base unit. It is plugged into the wall using the supplied adapter. Any ideas or do I have a defective unit? Thanks in advance.