Is that a teapot or is it just your hearing aids? Feedback is a very common problem with hearing aids but it’s not something that you can’t have fixed. Knowing exactly how hearing aids work and what might be the reason for that annoying whistling sound will get you one step closer to eliminating it. What can you do about hearing aid feedback?
How Do Hearing Aids Work?
A simple microphone and a speaker are the core of hearing aid technology. When a sound is picked up by the microphone, the speaker then plays it back in your ears. When the microphone picks up the sound but before it gets played back by the speaker, there are some complex functions that happen.
After the sound is picked up by the microphone it is modified into an electrical analog signal to be further processed. The analog form is then converted into digital by the device’s processor. The sound is cleaned up after it becomes digital by the device’s functions and settings.
The digital signal processor then transforms the signal back to analog and forwards it to a receiver. Now, what was once a sound wave becomes an analog electrical signal and that isn’t something your ears can hear. The receiver converts the signal back into sound waves and sends them through your ear canal. Elements in the cochlea translate it back into an electrical signal that the brain can interpret.
Amazingly all of this complex functionality takes place in a nanosecond. Despite all of this state-of-the-art technology, the device still has feedback.
Feedback Loops And How They Happen
Feedback doesn’t exclusively happen in hearing aids. Systems that come with microphones usually have some amount of feedback. The receiver puts out sound which the microphone then picks up and re-amplifies. The sound wave enters the microphone, goes through the processing and then the receiver turns it back into a sound wave. A feedback loop is then created when the microphone picks up the sound again and re-amplifies it. Simply put, the hearing aid is hearing itself and doesn’t like it.
What Causes Hearing Aid Feedback?
A feedback loop may be brought about by several issues. A very common cause is turning the hearing aid on while it’s still in your hand and then putting it in your ear. Your hearing aid starts to process sound as soon as you hit the “on” switch. This feedback is caused as the sound coming from the receiver bounces off your hand and right back into the microphone. The solution to this concern is very simple; wait until after the device is snuggly in your ear before hitting the switch.
Occasionally hearing aids won’t fit as well as they ought to and that can lead to feedback problems. If you have lost weight since you last had your hearing aids fitted, or possibly if your hearing aids are older, you might have a loose fit. Getting an adjustment from the seller is the only real answer to this problem.
Earwax And Feedback
Hearing aids certainly have problems with earwax. Earwax accumulation on the casing of the hearing aid keeps it from fitting right. And we are already aware that a loose fitting device will be the cause of feedback. If you consult your retailer or perhaps if you study the manual, you will determine how to safely clean this earwax off.
Perhaps It’s Only Broke
If all else doesn’t work you need to consider this. A damaged hearing aid will definitely cause feedback. The casing may have a crack in it somewhere, for example. It’s unwise to try to fix the unit yourself. Schedule an appointment with a hearing aid specialist to get a repair.
When is Feedback Not Actually Feedback
Hearing aids will make other noises that sound like feedback but are actually something else. Some hearing aids employ sound to warn you of imminent problems such as a low battery. The sound should be carefully listened to. Is it a tone or a beep, or does it actually sound like feedback? Consult the manual to find out if your device has this feature and what other warnings you should listen for in the future.
Feedback doesn’t discriminate by brand or style. Usually, the actual cause of the feedback is quite clear no matter what brand you own.