When speaking with individuals that use hearing aids, a problem that we hear about from time to time is users who say that voices “sound strange.” The following article, posted on hear-it.org, explains this phenomenon:
When you first use hearing aids you may find that your voice sounds strange to you. The voice may sound hollow or booming as if you were talking in a barrel.
This phenomenon is known as the occlusion effect. The voice distortion is so annoying to some hearing impaired people that they leave their hearing aids unused even though a few simple adjustments may take care of this problem in most cases.
Blocked passageway
The problem occurs when the hearing aid ear mold completely fills the ear canal trapping the vibrations from your own voice in the ear. Instead of escaping the ear, the vibrations bounce off the blockage and stay in the ear making the voice appear louder. In the lower frequencies the voice may be amplified as much as 20 dB.
In most cases, creating a vent through the hearing aid to unblock the ear solves the problem. This allows the vibrations of your own voice to escape the ear. A larger vent promotes a more normal sounding voice.
Some hearing aids come with a pressure relief vent, equalizing the air pressure in the ear, but these vents are often too small to reduce the occlusion effect. Thus, it may be necessary to create a larger passage in the hearing aid.
Continue reading this article, posted on hear-it.org, by clicking here, and find out what adjustments can be made to combat the occlusion effect.
Source: http://www.hear-it.org/

The study, published online February 28th in the Journal of Gerontology: Medical Sciences, concluded that additional research is needed to determine why black race is protective against hearing loss. 
