Hi Sally5343,
welcome to this Apple (user-to-user) Community :-)
Re: "Phonak battery operated hearing aids: Even when my hearing aids are connected in the phonak app and i manage to pair them on bluetooth , although this is v unstable as they disconnect fairly often, the sound still doesn't go to my hearing aids but continues on the phone speaker. "
Seems Phonak doesn't produce any "Made for iPhone" models:
List of Made for iPhone hearing devices - Apple Support
So without Mfi compatibility, you would likely need to rely on the manufacturer's app for control.
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Re: What can I do? Are there settings on my iPhone 14 I need to change?
Wondering whether it is in phone calls, or when streaming music, or ?, that you need to direct the audio to the hearing-aids.
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Manually for phone calls: Change the audio to the hearing-aids during an actual call
Apple Support's online article: While on a call on iPhone - Apple Support
Eg: says:
Adjust the audio during a call
To change the volume, press the volume buttons on the side of iPhone. Or swipe down on the call banner, then do any of the following:
- Mute: Tap the Mute button.
- Put the call on hold: Touch and hold the Mute button.
- Talk handsfree: Tap the Audio button, then choose an audio destination.
(NB: See if you can choose your hearing-aids there.)
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Automatically for Phone calls
We don't know which iOS version is installed on your iPhone:
For iOS 26: (or please choose the correct iOS version at the top of article below for accurate info.)
See if you can: Route and automatically answer calls on iPhone - Apple Support
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Re: " .... they disconnect fairly often"
If your hearing-aids won't stay connected wirelessly, there might be interference with other wireless devices. See how to:
Resolve Wi-Fi and Bluetooth issues caused by wireless interference - Apple Support
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Else: You might want to take a look at Phonak's compatibility webpage:
You can enter an iPhone model to see what info & advice they make available online:
https://www.phonak.com/en-int/support-options/phone-compatibility
All the best :-)