The microphone is located on the underside of the button—it is a small hole around the size of a pen tip. Make sure the microphone is uncovered when you are recording. If the microphone is covered while recording, it produces static.
By experimenting with the volume of your voice and the position of the button while you’re recording, you can significantly improve the button audio quality and reduce distortion.
When speaking too close to the microphone, the microphone can be overpowered—causing the playback to be significantly distorted. Speak clearly, but not particularly loudly. The button will adjust its volume to compensate if the volume is low, but it can’t compensate for volume that’s too high. Because of the button’s size, higher-pitched sounds tend to be better reproduced than lower ones, so adjusting the pitch of your voice can also be a way of improving the audio the button produces. Getting it just right can take a few attempts.
Here are few more tips that could lead to better results:
Pause just a split second after the beep so you don't cut the beginning of your word off
Don't breathe into the mic as you record
Try to articulate your words while still keeping the same natural rhythm and tempo you normally would to say the word
Avoid background noise- don't stand near appliances, fans, windows, air ducts, etc. that might contribute to extra noise