Does your hearing aid sound a bit like a teakettle these days? Feedback is a common concern with hearing aids but it’s not something that can’t be fixed. Knowing how hearing aids operate and what is behind that constant whistling sound will get you a little closer to eliminating it. What can you do about hearing aid feedback?
What Exactly Are The Functions of Your Hearing Aids?
Hearing aids, basically, are really just a microphone and a speaker. The speaker plays back the sound into your ear that the microphone picks up. When the microphone picks the sound up but before it gets played back by the speaker, there are some intricate functions that occur.
Once a sound wave enters the microphone it is converted to an electrical analog signal for processing. A sophisticated conversion from analog to digital is then accomplished by a signal processing chip. The device’s advanced features and settings activate to amplify and clarify the sound.
The processor then changes the signal back to analog and forwards it to a receiver. Now, what was once a sound becomes an analog signal and that isn’t something your ears can hear. The waves of sound, that the receiver changes the signal back to, are then sent through your ears. Ironically, the brain interprets sound by electrical signals, so elements in the cochlea turn it back to electrical signals for the brain to understand.
Surprisingly all of this complex functionality takes place in a nanosecond. So if your hearing aid is so advanced why does it feedback?
Feedback Loops And How They Happen
Feedback occurs in other sound systems besides hearing aids. If the sound system uses a microphone, chances are there is some feedback. Essentially, the microphone is collecting sound that is coming from the receiver and re-amplifying it. After going into the microphone and being processed, the receiver then transforms the signal back into a sound wave. The microphone then picks up that same sound wave again and amplifies it generating the feedback loop. The system doesn’t like hearing itself over and over again and that makes it screech.
Exactly What is The Cause of Hearing Aid Feedback?
There are several things that can go wrong to create this feedback loop. If you turn on your hearing aid while it’s still in your hand before you put it in, you will get a very common cause. Right when you push the on button, your hearing aid starts to process sound waves. The sound coming from the receiver bounces off your hand and then back into the microphone producing the feedback. If your hearing aid is snuggly inside of your ear and then you turn it on, you will have resolved this particular feedback concern.
If your hearing aids aren’t fitting as well as they should, this can also lead to feedback. Loose fitting devices have a tendency to be a problem with older hearing aids or if you’ve lost weight since you last had them fitted. Getting it adjusted by the retailer is the only good solution to this problem.
Earwax And Feedback
When it comes to hearing aids, earwax is in no way a friend. One of the major reasons that hearing aids don’t fit right is because of the accumulation of earwax on the casing. When that occurs, the device becomes loose again and causes feedback. If you ask your retailer or maybe if you read the manual, you will determine how to safely clean this earwax off.
Perhaps It’s Just Broken
If all else doesn’t work you need to consider this. Feedback can definitely be caused by a damaged hearing aid. For instance, the outer casing might be cracked. It’s unwise to try to fix it on your own. Schedule a session with a hearing aid repair service to have it fixed.
When is Feedback Not Actually Feedback
You may well be hearing something that you think sounds like feedback but it’s really not. Many hearing aids use sound to alert you of impending problems such as a low battery. Pay attention to the sound. Is it a tone or a beep, or does it really sound like feedback? Consult your users-manual to see if your device includes this feature and what other warnings you should listen for in the future.
It doesn’t make a difference what brand or style you have. Typically, the cause of the feedback is quite clear no matter what brand you have.