ReSound Hearing Aid Whistling Feedback — Fix Guide

What Does This Error Mean?

Whistling on ReSound hearing aids is sound leaking back into the microphone — usually caused by a poorly fitting dome, earwax buildup, or volume too high. Check the dome fit and clean the aid first.

Affected Models

ReSound ONE
ReSound Nexia
ReSound Omnia
ReSound Linx Quattro
ReSound Key

Common Causes

Dome too small or worn — sound leaks around it
Earwax buildup in the ear canal reflecting sound back
Volume turned up too high
Hearing aid microphone covered or blocked
Receiver tube damaged or loose

How to Fix It

Check the dome fit.

The dome (the soft tip on the end of the receiver) should fit snugly in your ear canal. If it slides out easily or you feel air leaking around it, you need a larger dome size. Your audiologist can supply different sizes.
Inspect for earwax buildup.

Even a small amount of wax in the ear canal causes feedback. Have your ears checked by a doctor or audiologist. Do not use cotton buds — they push wax deeper.
Lower the volume.

Use the Smart 3D app or the rocker on the aid to lower volume by a step or two. If this stops the whistling, the aid is amplifying louder than your fit can support — see your audiologist for adjustment.
Clean the wax filter.

ReSound aids have a tiny wax filter at the end of the receiver. Replace it using the wax tool that came with the aids. A blocked filter changes sound output and can contribute to feedback.
Re-run feedback calibration.

In the Smart 3D app, run the in-ear calibration feature. This lets the aid learn your specific ear canal acoustics and reduce feedback. Repeat after a fresh dome fitting.

When to Call a Professional

Persistent whistling after dome and cleaning checks usually means a fit issue. Your audiologist can fit a different dome size or perform an in-ear feedback calibration.