Does your hearing aid sound a bit like a teakettle these days? A very common concern with hearing aids which can probably be fixed is feedback. If you would like to come one step closer to understanding why you keep getting that high pitch whistling noise, you should try to learn how your hearing aids operate. So what can you do about it?
What Exactly Are The Functions of Your Hearing Aids?
A simple microphone and a speaker are the basics of a hearing aid. When a sound is picked up by the microphone, the speaker then plays it back. When the microphone picks up the sound but prior to when it gets played back by the speaker, there are some complex functions that happen.
The sound is changed into an analog signal to be processed after entering the microphone. A high-tech digital processing chip then changes the analog signal to digital. The sound is cleaned up after it becomes digital by the device’s features and controls.
The signal is sent to a receiver after being changed back to analog by the digital signal processor. Now, what was once a sound becomes an analog signal and that’s not something your ears can hear. The waves of sound, which the receiver converts the signal back into, are then sent through your ear canal. Ironically, the brain interprets sound by electrical signals, so elements in the cochlea translate it back into electrical signals for the brain to understand.
It’s hard to comprehend but all of this happens in a nanosecond. So if your hearing aid is so advanced why does it still feedback?
Feedback Loops And How They Happen
Feedback doesn’t exclusively happen inside of hearing aids. You hear that same whistle in most sound systems which utilize a microphone. The receiver generates sound which the microphone then picks up and re-amplifies. The sound wave goes into the microphone, then goes through the signal processing and then the receiver turns it back into a sound wave. The microphone starts to pick up that same sound wave again and amplifies it producing the feedback loop. The hearing aid hates hearing itself over and over again and that causes it to screech.
What Causes Hearing Aid Feedback?
There are several things that could go wrong to cause this feedback loop. A very common cause is turning the hearing aid on while it’s still in your hand and then putting it in your ear. Right when you push the on button, your hearing aid begins processing sound waves. This feedback is caused as the sound coming from the receiver bounces off your hand and right back into the microphone. The solution to this difficulty is very simple; you should wait until after the device is inside your ear before hitting the switch.
Occasionally hearing aids don’t fit quite as well as they should and that leads to feedback problems. Maybe you’ve lost some weight since you had your hearing aids fitted, or if your hearing aids are older, you might have a loose fit. If that’s the case, you need to go back to the retailer and have the piece adjusted to fit your ear properly again.
Earwax And Feedback
Earwax isn’t a friend when it comes to hearing aids. Earwax buildup on the casing of the hearing aid keeps it from fitting right. When that occurs, the device is once again loose and triggers feedback. Look in the manual that came with your hearing aids or ask the retailer to find out how to clean earwax off safely.
Perhaps It’s Just Broke
This is your next thing to start thinking about when you’ve attempted everything else. A broken hearing aid will definitely feedback. For instance, the outer casing might be cracked. You should not attempt to fix this at home. Schedule a session with a hearing aid repair service to have it fixed.
When is Feedback Not Actually Feedback
There is a chance that what you are hearing is actually not really feedback at all. Some hearing aids use sound to alert you of imminent issues such as a low battery. The sound should be carefully listened to. Is it a tone or a beep, or does it really sound like feedback? If your device has this feature, the owners manual will tell you.
It doesn’t make a difference what brand or style you own. Many brands of hearing aids are going to produce it and the cause is usually pretty clear.