Disappointing right from the start

The first thing I tried was heating water for a cup of tea, which seemed a nice and easy way to begin, using the Lunch/Soup setting. We were amazed at the utter silence of the unit. More about that later. After too short a period of time, the unit shut off, and the clock numberals disappeared to be replaced by a series of dashes. The water was barely more than warm. Reading the directions, again, I wondered whether the silence was due to the fan not running. Next I tried to defrost a pound of beef. It came out still half frozen. Later in the day I tried another cup of water hoping I had simply made some sort of mistake during my first attempt. Same result as the first time: not warm enough and the machine shut down, the clock 'time' disappeared and was replaced by the dashes. I decided to test the fan by putting fresh water in, and turning on the machine manually for 2 minutes on power level 10. Then I held a kleenex beside the vent on the side of the machine. It never moved. It appears the fan does not work, along with disappointing results. Also, the rotating table always starts off with an odd jerky movement.
    At this point, I give up. It goes back to the store tomorrow. I'll still try another GE because our previous GE Profile gave great service for 6 years. At this moment I'm eyeing the JEB 1860MSS.  I'll let you know how it works. So far the reviews seem favorable.