Woman suffering from feedback in her hearing aids covering her ears.

Is that a teakettle or is it just your hearing aids? Feedback is a very common issue with hearing aids but it’s not something that can’t be fixed. Understanding exactly how hearing aids work and what might be the reason for that annoying high pitched whistling noise will get you one step closer to eliminating it. So what can you do about it?

What Exactly Are The Functions of Your Hearing Aids?

As a basic rule, hearing aids are just a microphone and a speaker. When a sound is picked up by the microphone, the speaker then plays it back in your ears. But there are intricate 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 transformed into an electrical analog signal. A sophisticated transformation from analog to digital is then done by a signal processing microchip. Once digital, the various features and controls of the device start working to intensify and clarify the sound.

The signal is transmitted to a receiver after being modified back to analog by the digital signal processor. You’re ears don’t hear these electrical signals which were once a sound. The receiver converts it back into sound waves and transmits them 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.

Amazingly all of this complicated functionality takes place in a nanosecond. So if your hearing aid is so advanced why does it still feedback?

How do Feedback Loops Occur?

Feedback doesn’t exclusively happen inside of hearing aids. If the sound system uses a microphone, most likely there is some amount of feedback. The receiver produces sound which the microphone then picks up and re-amplifies. After entering the microphone and being processed, the receiver then converts the signal back into a sound wave. A feedback loop is then created when the microphone picks up the sound again and re-amplifies it. The system hates hearing itself over and over again and that makes it scream.

Exactly What is The Cause of Hearing Aid Feedback?

A feedback loop may be caused by several issues. If you turn on your hearing aid while it’s still in your hand prior to putting it in, you will get one of the most common causes. Your hearing aid begins processing sound as soon as you hit the “on” switch. The sound being produced by the receiver bounces off your hand and then back into the microphone generating the feedback. If your hearing aid is snuggly in your ear and then you turn it on, you will have eliminated this particular feedback issue.

In some cases hearing aids won’t fit as well as they should and that leads to feedback. Loose fitting devices have a tendency to be a problem with older hearing aids or if you’ve lost some weight since you last had them fitted. If that’s the case, you need to go back to where you got it and have the piece adjusted so it will fit your ear properly again.

Earwax And Feedback

Hearing aids absolutely have problems with earwax. Hearing aids won’t always fit well if there is earwax built up on the casing. When that takes place, the device becomes loose again and causes feedback. If you get in touch with your retailer or maybe if you study the manual, you will determine how to safely clean this earwax off.

Perhaps It’s Only Broken

When you’ve tried everything else but the feedback continues, this is where you head next. A broken hearing aid will definitely cause feedback. For example, the outer casing may be cracked. You should not attempt to fix this damage at home. Schedule a session with a hearing aid repair service to get it fixed.

Sometimes What Sounds Like Feedback is Actually Something Else Entirely

You could be hearing something that sounds like feedback but it’s really not. A low battery or other potential problems will cause a warning sound in some devices. Listen closely to the sound. Is it a tone or a beep, or does it actually sound like feedback? Check your manual to find out if your device has this feature and what other warning sounds you should listen for in the future.

Feedback doesn’t discriminate by brand or style. Many brands of hearing aids are going to produce it and the cause is typically pretty clear.