Overview

The good news is that if you're dealing with a whistling hearing aid, it's relatively easy to fix. It all starts with knowing what's causing it. We'll go over six of the most common reasons your hearing aid's performance might suffer.
Man with whistling problems in his hearing aid

Your Earpiece Isn't Properly Fitted

Here's one of the biggest reasons why it's important to consult a professional audiologist when setting out to purchase a hearing aid. A device that isn't properly fitted to your ear canal can leave a small gap that allows air and sound waves to pass through. This, in turn, can cause a sound to be amplified repeatedly by the hearing aid's microphone.

Generally, feedback of this nature will grow increasingly louder until you either remove the hearing aid or the sound is no longer present. 

Your Hearing Aid Isn't Properly Configured

If a hearing aid hasn't been properly set up, it can transmit feedback that sounds surprisingly similar to that created by a damaged, faulty, or poorly-fitted one. Most modern hearing aids allow you to manually adjust their settings on your own. All the same, we'd still advise you to visit your audiologist so you can be certain you're making the proper tweaks.

Your Ears Are Dirty

In most cases, the ears are self-cleaning, and you don't need to do anything extra to keep them in good condition. However, in some cases, particularly if you're using a hearing aid, you might be suffering from excessive earwax buildup.  You can either use a cerumen softener, rinse regularly with warm water, or visit a doctor for an ear cleaning.

Whatever you do, avoid using cotton swabs. And while you're at it, clean your hearing aid every night before you go to sleep. 

A Blocked Sound Tube

Have you been properly cleaning your hearing aid? If not, the sound tube may have become blocked, meaning it cannot properly transmit sound. Try cleaning the device thoroughly, and if that doesn't work, bring it to your audiologist to determine if the sound tube needs to be replaced.

Clothing

Believe it or not, scarves and hats have been known to cause interference with some types of hearing aids. Hugging someone or physical closeness to a person of any kind can also cause temporary interference. If the whistling isn't constant, think about situations in which it tends to happen.

Your Hearing Aid is Faulty or Damaged

If you've gone through an exhausting troubleshooting process and still can't figure out what's wrong with your hearing aid, then there's a chance it may either be faulty or damaged. Either way, your only recourse at this point is to contact a professional audiologist to take a look at it.
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