Does your hearing aid sound a bit like a teakettle recently? Feedback is a very common problem with hearing aids but it’s not something that can’t be fixed. Understanding how hearing aids function and what might be the reason for that incessant whistling will get you one step closer to getting rid of it. What can be done about hearing aid feedback?
How Do Hearing Aids Work?
A simple microphone and a speaker are the basics of a hearing aid. The speaker plays back the sound in your ear that the microphone picks up. 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.
Once a sound wave is picked up by the microphone it is translated into an electrical analog signal for processing. A high-tech digital signal processing microchip then converts the analog signal to digital. Once digital, the numerous features and settings of the hearing aids kick in to intensify and clarify the sound.
The signal is transmitted to a receiver after being changed back to analog by the processor. At this stage, what was once a sound becomes an analog signal and that’s not something you can hear. The receiver converts the signal back into sound waves and transmits them through your ears. Elements in the cochlea translate it back into an electrical signal that the brain can interpret.
It’s hard to believe but all of this happens in a nanosecond. Despite all of this sophisticated technology, the hearing aid still feeds back.
Feedback Loops And How They Happen
Feedback doesn’t exclusively happen in hearing aids. If there is a microphone, it’s likely there is some amount of feedback. The receiver generates sound which the microphone then picks up and re-amplifies. The sound wave goes into the microphone, goes through the processing and then the receiver transforms it into a sound wave. The microphone then picks up that same sound wave again and amplifies it creating the feedback loop. Put simply, the hearing aid is listening to itself and doesn’t like it.
Exactly What is The Cause of Hearing Aid Feedback?
A feedback loop might be created by several issues. If you turn on your hearing aid while it’s still in your hand before you put it in, you will get one of the most common causes. Your hearing aid begins processing sound waves as soon as you press the “on” switch. The sound coming from the receiver bounces off your hand back into the microphone generating the feedback. When your hearing aid is snuggly inside your ear before turning it on, you will have resolved this particular feedback hassle.
Feedback is sometimes caused when your hearing aid doesn’t fit as well as it should. If you have lost weight since you last had your hearing aids fitted, or if your hearing aids a bit older, you may have a loose fit. Getting an adjustment from the retailer is the only real remedy to this problem.
Feedback And Earwax
Hearing aids absolutely have problems with earwax. One of the major reasons that hearing aids don’t fit properly is because of the accumulation of earwax on the casing. Now, feedback is once again being caused by a poor fit. Read the manual that you got with your hearing aids or ask the retailer to find out how to clean earwax off safely.
Perhaps It’s Only Broken
If everything else doesn’t work you need to take this into consideration. A damaged hearing aid will indeed cause feedback. The casing may have a crack in it somewhere, for example. Don’t try to fix the unit yourself. Take it in for expert repair.
When is Feedback Not Really Feedback
There is a possibility that what you are hearing is actually not feedback to begin with. There are things that can go wrong with your hearing aids, such as a low battery, which can give you a warning sound. The sound should be carefully listened to. Is it a tone or a beep, or does it actually sound like feedback? Consult your manual to find out if your device comes with this feature and what other warnings you should listen for in the future.
It doesn’t matter what brand or style you have. Many brands of hearing aids are capable of producing it and the cause is usually pretty clear.