Purchased to make fruit smoothies. I have been using frozen fruit and 1/4 cup of cold liquid and by the time the fruit is blended the drink is WARM. Not what I want. Also I have to take it off the base and shake it vigorously 3 or 4 time and blend at least two 2 minute cycles to not have chunks of frozen fruit in my drink, again not what I wanted. What am I doing wrong?