S-1.  Ensure that mic is correctly positioned--1/4 inch from corner of mouth

S-2.  Perform a background noise check ("sample noise", "noise check" or press button)

S-3.  Make sure you are using your own voice file (or "voice templates")

S-4.  Re-train the problem word.

S-5   Try a different headset to make sure that isn't the problem

S-6.  Re-train from scratch (last resort)