I have the same problem too, it always happened when the clutching of compressor is too rapid especially during raining day. What I did normally is to set the temp. a bit higher. I was told by 'insider' that it is something to do with the compressor which is an item that was not assemble in Korea. Maybe you can verify this during workshop clinic conducted by Korean 'specialist' in S'pore, which I did but I had a lot of argument than problem solving.