I received the Electret Microphone Amplifier yesterday and was experimenting with the Arduino. The range of values I'm getting back seems to indicate that it's not really picking up normal sound. I've tried adjusting the gain potentiometer with no better results. This is true at 3.3v and 5v. Blowing on the microphone will cause it to return values covering the entire range, but normal speech and yelling are essentially the same as silence from an output standpoint. Am I doing something wrong or do I have a bum part?
https://www.adafruit.com/products/1063

