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

Does your hearing aid sound a bit like a teakettle recently? Feedback is a very common concern with hearing aids but it’s not something that can’t be fixed. The irritating high pitched sound can be better understood by learning how your hearing aids work. But exactly what can you do about it?

What Exactly Are The Functions of Your Hearing Aids?

Hearing aids, at their core, are really just a microphone and a speaker. The microphone picks up the sound and the speaker plays it into your ear. It’s what happens between the microphone and speaker that becomes a little complicated.

In order for the sound to be processed, it must first be translated into an analog signal. A high-tech digital processing chip then converts the analog signal to a digital one. The sound is clarified after it becomes digital by the device’s functions and settings.

The processor then changes the signal back to analog and forwards it to a receiver. At this stage, what was once a sound becomes an analog electrical signal and that’s not something you can hear. The waves of sound, which the receiver converts the signal back to, are then transmitted through your ears. Ironically, the brain interprets sound by electrical signals, so elements in the cochlea translate it back to electrical signals for the brain to understand.

It’s hard to comprehend but all of this happens in a nanosecond. What goes wrong to cause the feedback whistle, though?

Feedback Loops And How They Happen

Feedback happens in other systems besides hearing aids. You hear that same whistle in the majority of sound systems that utilize a microphone. The receiver generates sound which the microphone then picks up and re-amplifies. The sound wave goes into the microphone, then goes through the signal processing and then the receiver transforms it into a sound wave. The microphone then picks up that sound wave again and amplifies it producing the feedback loop. Simply put, the hearing aid is hearing itself and it doesn’t like it.

What Causes Hearing Aid Feedback?

A feedback loop can be brought about 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 a very common cause. Right when you push the on switch, your hearing aid begins processing sound waves. The feedback is produced when the sound coming out of the receiver bounces off of your hand and then right back into the microphone. When your hearing aid is snuggly inside your ear before turning it on, you will have resolved this particular feedback problem.

Feedback can also be caused when your hearing aid doesn’t fit properly. Loose fittings have a tendency to be a problem with older hearing aids or if you’ve lost weight since having them fitted. Getting it adjusted by the seller is the only good solution to this problem.

Feedback And Earwax

When it comes to hearing aids, earwax is in no way a friend. One of the main explanations for why hearing aids don’t fit right is because of the accumulation of earwax on the casing. Now, feedback is again being caused by a loose fit. Look in the manual that came with your hearing aids or consult the retailer to find out how to clean earwax off without damaging the device.

Perhaps It’s Just Broke

This is your next thing to think about when you’ve attempted everything else. Feedback can certainly be caused by a damaged hearing aid. The casing could have a crack in it somewhere, for example. You should never try to fix this at home. Instead take it in for expert repair.

When is Feedback Not Actually Feedback

Hearing aids can make other noises that you may think sound like feedback but are in fact something else. There are a few other things that can go wrong with your hearing aids, like a low battery, which will give you a warning sound. The sound should be carefully listened to. Is it really a whistling noise or does it sound more like a beep? Check your manual to find out if your device has this feature and what other warning sounds you should pay attention to in the future.

It doesn’t make a difference what brand or style you have. Most hearing aids are going to produce it and the cause is usually pretty clear.