Is that a teakettle or is it just your hearing aids? A very common issue with hearing aids which can most likely be corrected is feedback. Knowing exactly how hearing aids function and what is behind that constant whistling sound will get you a little closer to eliminating it. But exactly what can be done?
How Do Hearing Aids Work?
A simple microphone and a speaker are the basics of hearing aid technology. The speaker plays the sound into 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 intricate functions that happen.
The sound is then transformed to an analog electrical signal for processing after entering the microphone. The analog version is then converted into a digital signal by the device’s digital signal processor. The sound is cleaned up after it becomes digital by the device’s functions and controls.
The digital signal processor then changes the signal back to analog and transmits it to a receiver. At this point, what was once a sound becomes an analog electrical signal and that isn’t something you can hear. The receiver converts it back to sound waves and sends them through your ear canal. Ironically, the brain interprets sound by electrical signals, so elements in the cochlea turn it back to electrical signals for the brain to understand.
Amazingly all of this complex functionality takes place in a nanosecond. Despite all of this state-of-the-art technology, the hearing aid still has feedback.
How do Feedback Loops Happen?
Feedback happens in other systems besides hearing aids. Sound systems that come with microphones typically have some level of feedback. Basically, the microphone is collecting sound which is produced by the receiver and re-amplifying it. The sound wave goes into the microphone, then goes through the processing and after that the receiver transforms it into a sound wave. The sound is re-amplified after the microphone picks it up again which creates a loop of feedback. The system hates hearing itself over and over again and that causes it to screech.
Exactly What is The Cause of Hearing Aid Feedback?
A feedback loop may be created by several difficulties. If you turn your hearing aid on in your hand before you put it in, you will get a very common cause. Right when you push the on switch, your hearing aid begins processing sound. This feedback is caused when the sound coming from the receiver bounces off of your hand and then back into the microphone. Before you turn your hearing aid on put it inside of your ear to eliminate this source of feedback.
Occasionally hearing aids won’t fit quite as well as they ought to and that leads to feedback. If you have lost weight since you last had your hearing aids fitted, or if your hearing aids are older, you may have a loose fit. Getting it adjusted by the retailer is the only good remedy to this one.
Feedback And Earwax
Earwax isn’t a friend of your hearing aids. Earwax buildup on the outer casing of the hearing aid keeps it from fitting right. When that happens, the device becomes loose again and produces feedback. If you ask your retailer or perhaps if you read the manual, you will learn how to safely clean this earwax off.
Perhaps It’s Simply Broke
When you’ve attempted everything else but the feedback continues, this is what you do next. A broken hearing aid will indeed cause feedback. For instance, the outer casing may be cracked. You should never attempt to fix this at home. Make an appointment with a hearing aid specialist to get a repair.
When is Feedback Not Actually Feedback
You might be hearing something that you think sounds like feedback but it’s really not. Many hearing aids use sound to alert you of imminent issues such as a low battery. The sound should be carefully listened to. Is it actually a whistling noise or does it sound more like a beep? If your device includes this feature, the manual will tell you.
It doesn’t matter what brand or style you own. Many brands of hearing aids are going to produce it and the cause is typically quite clear.