Poor Microphone Audio Quality with Bose MIE2i iPhone 3G

After reading rave reviews about this headset I went ahead and ordered it. Its very comfortable and for audio listening its really great and very comfortable. However the microphone audio quality is awful and I have reason to believe that its not the MIE2i thats the issue here. If I use the Voice Memo App to record a memo the audio quality with the headset is fantastic. Now if I make a phone call using the headset the other callers say the audio quality is awful and I should throw the headset in the garbage. Now if the headset was that bad then why am I getting good results with the voice memo app.
iPhone 3GS iOS 4 4.2