I’m sure most people reading this have been to a meeting, conference, play or concert when, out of the blue, you hear a really high pitched whistling noise over the speakers!! The person using the microphone has often moved too close to the speakers or amplifiers – causing the feedback. You can’t help but wince and put your hands over your ears quickly!
If you have worn hearing aids, you will have experienced whistling or feedback at some stage. It could have been triggered by you walking through a narrow doorway, bending down to pick something up, or perhaps putting on a hat or cap! Even giving someone a hug – something we are all missing desperately during this pandemic!
The reason this happens is a fairly simple one. Amplified sound that was going into your ear canal from the hearing aid can escape from the canal, and gets picked up again by the microphone. It is then reamplified by the aid and that is why it whistles – or feeds back!
Even simple moves like putting your hearing aids in during the morning, or removing them at night can cause degrees of whistling. This is perfectly normal – it’s just the aids reacting to the sounds bouncing about around you. It doesn’t necessarily mean the aids are faulty, but they could be. They may simply need cleaning, but you may also need to see one of our audiologists or receptionists to see if the problem can be rectified. Our contact numbers are given at the top of our website pages.
Causes of feedback and can you do anything?
The newest hearing aid technology invariably has what is known as “feedback cancellation” built into the software programming. If an aid starts to whistle, this process normally would stop the whistling as soon as it starts.
However, there are other explanations which can cause whistling, and you may be able to prevent it.
a) Poor fitting – you may not have fitted the domes or the moulds in your ears properly. Your ears can also change shape over time, and if your moulds are old, they may not fit your ears properly now. You may have gained or lost weight, which may also affect the fitting in your ears. The sound could therefore be escaping from your ears, as explained before, and being reamplified – causing feedback. You may therefore need new moulds making, or different size domes fitted. Maybe a member of your family could have a look to check and see if it’s fitting neatly in your ear?
b) Too loud – if you turn your aids up too loud, then they are more likely to whistle. It is basically forcing the sound to be picked up again by the microphones – thus making them feedback. Turn the volume down and the whistling will go. If your hearing has changed and you need them adjusting then contact your hearing healthcare professional.
c) Split/hard tubing? If you have a behind the ear aid (either NHS or private) which has tubing rather than a receiver wire, then if it has hardened or split, sound can escape and be picked up by the microphone again – causing whistling as previously explained. The hard tube could also pull the mould loose in your ear – poor fitting as in point a) above. You may need the tube replacing or even a replacement mould.
d) Earwax? Your ears are producing wax all the time. Some people produce more than others. Your hearing aids send sound down your ear canal to your eardrums, but if there is too much wax in your canals, then the sound bounces back out of your ears and into the microphones – making them whistle! It is also likely that if your ears are completely blocked that some of it can ingress into the earpieces and block the output – effectively stopping them working. Arrange to get your ears cleared by water irrigation or microsuction – we can do that for you. In the meantime, check that the moulds, domes, receivers, air vents or wax filters aren’t blocked – you may just need to clean or replace them depending on what ear fitting you have.
e) Faulty or dislodged microphones – it is possible that the microphone in the hearing aid may be faulty and/or loose. If you believe this may be the case, then please contact your professional who will be able to rectify the issue for you.
Thank you for taking the time to read this. I hope it has been of some assistance to you to make your hearing health experience easier and more comfortable.