Your thyroid, a butterfly-shaped gland in your lower neck, pumps out a hormone that controls a number of functions in your body. When your thyroid doesn't make enough of it, one symptom you might have is a hoarse voice.
If you have a goiter -- an enlarged thyroid -- you may cough a lot and have problems with your speech. A growth on the thyroid, or a nodule, can also affect the way you speak.