I changed from using dome inserts to using custom ear molds, and ever since the swap my left ear has a very frequent whistling. It happens whenever anything gets near my ear; however, sometimes it will randomly whistle with nothing near my ear.
I swapped out the receivers today back to the domes and the whistling is completely gone.
My audiogram is on here, and I use the Phonak infinio sphere P90. I have tried anything I can think of: whistle block maxed for every program, every conceivable setting for noise block, and soft sound block.
Any suggestions would be very apppriciated. With the domes I can’t get anything to register at 250Hz, and I feel like I had a better hearing “range” when using the custom molds, but the whistling is unbearable. Also, the whistling never occurred in my right ear. Not even when, for testing purposes, jacked the volume way to high for my prescription.
Not all custom domes are created equally.
For instance, your ear canal changes when you move your jaw. E.g. when you talk while the 2-component silicone paste is hardening. The result can be space between the ear canal wall.
Anyway, feedback occurs, when the mic of your aids picks up on the sound generated by the receiver in your ear canal. So you’ve got a gab.
Get a new custom mold for the troublesome one or coat them repeatedly with a non-toxic paint (or even silicone diluted with terpentine) at the places that matter. I would prefer the last option, because the lab already messed up once and the second option is non-damaging and reversible.
As a fast check whether this would help, you can use a little 2-component silicone paste and spread it around your mold and place it in your ear. The excess should move to the tip of the mold and out of the ear and can be removed with a pencil knife after hardening.
I am going to try this with my custom molds. I’ve got molds with outer shells, that tend to rotate a bit. It would be nice to stop that. It would severely reduce the amount of ear wax that I generate since I have these moulds.
Apologies for the delayed response. To answer your question about the feedback issue—yes, I’ve dealt with it many times. In fact, I’ve probably run the feedback test around two dozen times trying to fix it, lol. Thanks for your suggestions! I’m planning to order the silicone paste and give your recommendation a shot. Right now, I’m using vented domes, but they’re far from ideal. For example, with these domes, I can’t even increase the decibel levels enough to hear properly from my left ear.