Why Do Hearing Aids Squeal? Causes and Fixes

That sharp whistle from your hearing aid can be startling, especially when it happens in the middle of a conversation. If you have wondered, “why do hearing aids squeal,” the usual answer is feedback: sound from the device escapes the ear, gets picked up by the microphone, and is amplified again. The good news is that occasional squealing is common and often easy to correct. Persistent feedback, however, deserves attention because it may mean your hearing aid fit, ear canal, or device settings have changed.

Why Do Hearing Aids Squeal?

Hearing aids are designed to make sounds louder and clearer. They do this by collecting sound through a microphone, processing it, and delivering it into your ear through a speaker. Feedback occurs when some of that amplified sound leaks out and travels back to the microphone. The device re-amplifies the sound, creating the familiar whistling or squealing noise.

A brief whistle when you put your hearing aid in, take it out, hug someone, hold a phone near your ear, or pull on a hat is not always a sign of a problem. In those moments, an object is close enough to redirect sound back toward the microphone. Many modern hearing aids have feedback-management features that reduce this quickly.

If the squealing continues while the hearing aid is correctly inserted and you are not touching it, there may be a fit, wax, or equipment issue worth checking.

Common Causes of Hearing Aid Feedback

The hearing aid is not seated properly

A hearing aid that is slightly loose or not fully inserted can let amplified sound escape. This is particularly common with custom earmolds, behind-the-ear devices, and receiver-in-canal styles with soft domes. Even a small gap can be enough to create feedback.

Try removing the hearing aid and inserting it again slowly, following the instructions you received at your fitting. With a dome-style device, make sure the dome is fully in the ear canal and has not folded over. With an earmold, check that it sits comfortably and securely in its usual position.

Earwax is blocking the ear canal

Earwax is one of the most frequent reasons a hearing aid that once worked well begins to whistle. When wax blocks the ear canal, sound cannot travel normally toward the eardrum. Instead, it can bounce back toward the hearing aid microphone.

Wax may also cause a plugged sensation, reduced clarity, or a change in how your own voice sounds. Some people assume the hearing aid needs to be turned up when the real concern is earwax. Increasing the volume may make feedback worse.

Avoid putting cotton swabs or other objects into the ear canal. They can push wax deeper and sometimes cause injury. A hearing care professional can look in your ears and recommend safe removal when needed.

The hearing aid needs cleaning or maintenance

Wax, moisture, or debris can collect in the wax guard, receiver, microphone ports, tubing, or earmold. This may affect sound quality and cause the hearing aid to behave differently than usual. A clogged wax guard more often causes weak sound, but buildup and damage can contribute to feedback as well.

Follow your daily cleaning routine, including changing wax guards and filters as directed for your specific hearing aid. If you use a behind-the-ear model with tubing, inspect the tubing for moisture, hardening, cracks, or a loose connection. Tubing does not last forever and may need professional replacement.

Your ear shape or hearing needs have changed

Ears can change over time. Weight changes, skin changes, healing after surgery, and normal changes in the ear canal can affect how an earmold or dome fits. If a custom earmold has become loose, sound may leak around it more easily.

Your hearing levels can change, too. When hearing aids need more amplification, managing feedback can become more challenging. That does not automatically mean you need new hearing aids, but it is a good reason to have your hearing and device programming reviewed.

A component may be damaged

A cracked shell, torn dome, loose receiver wire, damaged microphone, or split tubing can allow sound to escape or interfere with normal performance. Sometimes the issue is visible. Other times, the hearing aid may look fine but squeal because an internal component needs service.

If the feedback began suddenly after the device was dropped, exposed to moisture, stepped on, or chewed by a pet, do not keep adjusting the volume in an attempt to solve it. A professional inspection is the safer next step.

Something is close to the hearing aid

A hand cupped over the ear, a telephone held too close, eyeglasses, a scarf, a helmet, a face mask strap, or a high-backed chair can cause temporary feedback. This type of squealing usually stops when you move the object away.

If you wear glasses, make sure the arms of the frames are not pressing against the hearing aid or pushing it out of position. If feedback occurs during phone calls, ask your hearing care provider whether your hearing aids have a telephone setting, Bluetooth streaming option, or programming adjustment that could help.

What You Can Safely Try at Home

Start with the simplest checks. Turn the hearing aid off, remove it, and inspect it in good light. Confirm that the dome or earmold is clean, intact, and correctly attached. Look for a damaged wax guard, cracked tubing, or a receiver wire that is bent or loose.

Next, reinsert the hearing aid carefully. If you wear two hearing aids, check that each device is in the correct ear. Then turn it on at your usual volume. If the squeal happens only while you are handling the device, it may be normal insertion feedback. If it continues once the device is securely in place, do not force it deeper into your ear.

You can also replace a wax guard, filter, dome, or battery if your care plan and device instructions call for it. Rechargeable devices should be cleaned and dried before being placed in their charger. Moisture can affect performance, particularly after rain, heavy perspiration, or time outdoors in Manitoba’s changing weather.

Do not use tape, glue, or household tools to repair a hearing aid. A quick fix can damage the device further or make it unsafe to wear.

When Squealing Means It Is Time for an Appointment

Arrange a hearing aid check if feedback is frequent, loud, or new for you. It is especially helpful to book an appointment if reinserting and cleaning the device does not solve the issue, if you suspect wax buildup, or if your earmold feels loose.

You should also seek care promptly if squealing is accompanied by ear pain, drainage, sudden hearing changes, dizziness, or a feeling of significant pressure in the ear. Hearing aids do not cause every ear symptom, and an ear health concern may need separate evaluation.

At an appointment, a hearing care professional can inspect your ears, test the hearing aid, check the fit, clean or replace worn parts, and assess whether programming changes are appropriate. For some people, a slightly different dome size or a new earmold is enough. For others, feedback can be reduced through adjustment of amplification or the device’s feedback-control system. The right solution depends on your hearing loss, ear anatomy, hearing aid style, and everyday listening needs.

A Proper Fit Makes a Meaningful Difference

Hearing aids should support conversations, family time, work, and the sounds that help you feel connected to your surroundings. They should not leave you bracing for a whistle every time you move your head or answer the phone.

At Windsor Park Hearing Center, we encourage patients to bring up even small changes in comfort or sound quality. Ongoing hearing care is not just about purchasing technology. It is about making sure that technology continues to fit your ears, your hearing, and your life. If squealing has become part of your daily routine, a simple check may be all it takes to help your hearing aids sound comfortable and clear again.