If you are using an external microphone, make sure that it is connected properly to your sound card. After confirming the connection (or if you are using the built-in microphone), select SimpleSound (one of the accessories included with the Macintosh Operating System) from the Apple menu.
Activate SimpleSound and then select New from the File menu. The SimpleSound recording controls appear. Use the controls to record a sample of your voice. Rewind the recording and play it back. If the recording works with SimpleSound, it should work with eMail inChorus.
If there is too much static on your voice recordings, try to hold the microphone closer to your mouth when speaking. You can also try lowering the volume.