Does your hearing aid sound a little like a teakettle recently? Feedback is a very common problem with hearing aids but it’s not something that you can’t have fixed. Knowing how hearing aids function and what is behind that annoying whistling will get you a little closer to eliminating it. But exactly what can be done?
How Do Hearing Aids Work?
At their core, hearing aids are simply a microphone and a speaker. The speaker plays back the sound into your ear which the microphone picks up. When the microphone picks the sound up but prior to when it is played back by the speaker, there are some intricate functions that occur.
The sound is then transformed into an analog signal for processing after entering the microphone. A cutting edge digital processing chip then changes the analog signal to a digital one. The sound is clarified after becoming digital by the device’s features and settings.
The processor then transforms the signal back to analog and transmits it to a receiver. At this stage, what was once a sound wave becomes an analog signal and that’s not something your ears can hear. The waves of sound, which the receiver changes the signal back into, are then sent through your ear canal. Elements in the cochlea convert it back into an electrical signal that the brain can interpret.
Incredibly all of this complicated functionality happens in a nanosecond. In spite of all of this sophisticated technology, the device still feeds back.
Feedback Loops And How They Happen
Feedback doesn’t exclusively happen inside hearing aids. You hear that same high pitched noise in most sound systems that use a microphone. 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 after that the receiver transforms it into a sound wave. A feedback loop is then created when the microphone picks up the sound again and re-amplifies it. The hearing aid doesn’t like hearing itself over and over again and that causes it to screech.
Exactly What is The Cause of Hearing Aid Feedback?
There are several things that can become a problem which could cause this feedback loop. If you turn your hearing aid on in your hand prior to putting it in, you will get a very common cause. Right when you push the on button, your hearing aid begins processing sound. This feedback is produced as the sound coming from the receiver bounces off of your hand and back into the microphone. If your hearing aid is snuggly inside your ear before turning it on, you will have eliminated this particular feedback issue.
Feedback can also be caused when your hearing aid doesn’t fit properly. Loose fitting devices have a tendency to be a problem with older hearing aids or if you’ve lost some weight since having them fitted. Getting it adjusted by the seller is the only real solution to this problem.
Feedback And Earwax
When it comes to hearing aids, earwax is in no way a friend. Earwax accumulation on the casing of the hearing aid stops it from fitting right. When that happens, the device is once again loose and produces feedback. If you ask your retailer or if you read the manual, you will determine how to safely clean this earwax off.
Maybe It’s Just Broke
When you’ve attempted everything else but the feedback continues, this is what you do next. A broken hearing aid will definitely cause feedback. The casing might have a crack in it somewhere, for example. Don’t try and fix the unit yourself. Schedule an appointment with a hearing aid expert to get a repair.
When is Feedback Not Really Feedback
You could very well be hearing something that you think sounds like feedback but it’s actually not. A low battery or perhaps other potential issues will cause a warning sound in many devices. The sound should be carefully listened to. Is it actually a whistling noise or does it sound more like a beep? Check your users-manual to find out 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. Most hearing aids are capable of producing it and the cause is typically quite clear.