Why is There Feedback Coming From my Hearing Aids?
Is that a teakettle or is it just your hearing aids? A very common concern with hearing aids which can probably be fixed is feedback. The aggravating high pitched sound can be better comprehended by learning how your hearing aids operate. What can you do about hearing aid feedback?
How Do Hearing Aids Work?
At their core, hearing aids are just a microphone and a speaker. When a sound is picked up by the microphone, the speaker then plays it back. But there are advanced functions between the time that the microphone picks up the sound and when the speaker plays it back.
Because the sound is going to be further processed, it must first be turned into an electrical analog signal. A state of the art digital signal processing microchip then turns the analog signal to a digital one. Once the signal is converted to digital, the various features and settings of the hearing aids start working to amplify and clean up the sound.
The processor then transforms the signal back to analog and forwards it to a receiver. You’re ears don’t hear these electrical signals that were once a sound. The waves of sound, which the receiver changes the signal back to, are then transmitted through your ear canal. Ironically, the brain interprets sound by electrical signals, so elements in the cochlea turn it back into electrical signals for the brain to understand.
It all sounds quite complicated but it happens in a nanosecond. What happens to cause the feedback whistle, though?
Feedback Loops And How They Happen
Feedback happens in other systems besides hearing aids. If there is a microphone, it’s likely there is some feedback. The receiver puts out sound which the microphone then picks up and re-amplifies. The sound wave goes into the microphone, then goes through the processing and then the receiver turns it back into a sound wave. The microphone starts to pick up that sound wave again and amplifies it generating the feedback loop. The hearing aid hates hearing itself over and over again and that causes it to scream.
Exactly What is The Cause of Hearing Aid Feedback?
There are quite a few things that might become a problem which could create this feedback loop. A very common cause is turning the hearing aid on in your hand and then putting it in your ear. Your hearing aid begins processing sound right when you press the “on” switch. The sound coming from the receiver bounces off of your hand back into the microphone triggering the feedback. When your hearing aid is snuggly inside your ear before turning it on, you will have resolved this particular feedback concern.
Sometimes hearing aids won’t fit quite as well as they ought to and that leads to feedback. Loose fitting devices tend to be a problem with older hearing aids or if you’ve lost some weight since you last had them fitted. Getting an adjustment from the seller is the only good answer to this problem.
Feedback And Earwax
Earwax isn’t a friend of hearing aids. One of the major reasons that hearing aids don’t fit right is because of the buildup of earwax on the casing. And we already know that a loose fitting device will cause feedback. Read the manual that you got with your hearing aids or ask the retailer to determine exactly how to clean earwax off without damaging the device.
Maybe It’s Only Broken
When you’ve tried everything else but the feedback continues, this is where you head next. Feedback can definitely be caused by a damaged hearing aid. For example, the outer casing might be cracked. It’s unwise to try to fix it on your own. Schedule an appointment with a hearing aid specialist to get a repair.
When is Feedback Not Really Feedback
You may be hearing something that sounds like feedback but it’s actually not. A low battery or maybe even other potential issues can cause a warning sound in some devices. The sound should be carefully listened to. Is it a tone or a beep, or does it really sound like feedback? If your device includes this feature, the manual will tell you.
Feedback doesn’t discriminate by brand or style. Typically, the actual cause of the feedback is pretty clear regardless of what brand you have.