Can an iPhone communicate with a car sound system when in the car, and with hearing aids otherwise?

My audiologist says a phone cannot switch from car to hearing aids without human intervention, because “how would the car know when to produce sound and when not to?” My opinion is that the phone is in control and decides which device to connect with. Who is right?

You are. That’s how things work with my ReSound Preza aids.

I have Oticon OPN1 hearing aids and my phone switches automatically from my vehicle to my aids and pack to the vehicle

It is actually kind of complicated, but I believe basically you are right.

I have my iPhone MFi page, Audio Routing set up so Call Audio and Media Audio is set to be automatic. When like that media and phone call control switches to the my truck when the phone pairs with the truck. However, I have recently discovered that in iTunes if you have a selection of music playing and you touch that selection which is displayed at the bottom with pause and fast forward icons, it will bring up a full screen with the music album cover. At bottom center of the screen is an icon which displays where the audio is being sent. If you touch that icon it brings up another screen. There is a normally a choice there of overriding the auto and sending the audio to either the iPhone or my hearing aids. Then, if I am in my truck, there are three options. Truck, aids, iPhone. When I send it to the Truck, I have to select bluetooth as the audio source. But as I say by default it sends the media audio to my ears out of truck range, and to the truck when in it.

And if that is not complicated enough another little window comes up on the lock screen when playing iTunes. There is a blue icon there that also lets you select where you want the iTunes audio sent.

As for the phone call audio it switches from HA’s to the truck sound system automatically. By playing with the other two choices in MFi Audio Routing you may be able to change that. Have not tried…

Good thing we have all this complicated stuff to figure out or we would get bored with our hearing aids!

I have a KS8 aid, but I suspect none of this has to do with the KS8 aid app. It is just Apple MFi capability…

My OPN1s switch to the car when in the car and will put incoming and outgoing calls through the car sound system. But I notice that if I have my phone giving me driving directions, it will stream the map guidance to my ear rather than sending it through either the phone speaker or the car.

Thanks for the detailed explanation. Keeps me from getting bored.

I have the Garmin GPS that I put on top of my dashboard and normally I have the volume turned off. And I would think that it going to my hearing aids would be the ideal way

I have Marvels (M70-R’s) and the phone (Android Galaxy Note 9) switches over the the car Bluetooth when I start up the car to play music and phone calls through the car’s audio system.

Once I’m in a call, the Android call progress screen has an audio source selector so I can manually switch back to the HA’s if I want to or manually choose handset or speakerphone also.

The intelligence (in the case of the Android) is in the phone, and it makes the decision that when you’re in the car, the car audio takes precedence. Since the phone is multi-connectable, it maintains the connection with the HA’s to make it easy to switch back to them.

Notably, when the phone rings, it rings in the phone, through the car audio, AND through the HA’s. I might even be able to answer a call on the Marvels by pressing the volume rocker and override the phone’s default to the car audio. I’ll let you know if that’s the case after I try it.

A lot of your success in getting the switching done the way you want has to do with the car. There are so many variations within each brand, even models within each brand that it’s difficult to pinpoint. Then add the complexities of the different HA configurations? And many different types of phones! Universal compatibility is something we may never see because of proprietary technology and free market competition.

I have set my switching to manual because the car seems to get things wrong most (but not all) of the time. Just because someone else has great luck with a Toyota and the same HA model you have doesn’t mean it’s going to go well with an Audi or Nissan. Or a different year of the same model. Too many things are in constant change and have yet to be sorted out.

1 Like

What was your actual experience? Like, which phone, OS version, and what car, and what happened before you switched to manual?

In my case, iPhone XS with whatever was the latest iOS a month ago and a 2015 Subaru Outback. I assure you there would have been a different result with a 2017 (or later) Outback because the car software changed. Sometimes the phone would switch to output through my car audio, other times stay with my new hearing aids (Oticon S1). But I don’t drive that car very often or speak on the phone in the car that often and didn’t spend a lot of time sorting it out. It’s easy enough to just tap the screen on the phone to redirect any call that doesn’t just go where I want.

Having spent three decades testing and reviewing cars for a living, there are more variables there than with different hearing aids and difference phones. So the number of potential variations is astronomical.

Fortunately the iPhone makes it simple to transfer calls to the device I choose which, when in the car is the car audio. Each situation seems to work a little differently for me so when not driving I might prefer audio directly into the HAs one time but rather put the phone to my ear another, depending on the volume and type of background noise.

I’ve actually never had better phone audio quality than when using Apple AirPods. AirPods are also by far the best music audio quality I’ve experienced when fully mobile. They’re not quite a match for full coverage quality headphones (Bose QuietComfort 25 being the best I own) but I don’t like walking with those things on. And if I’m sitting at home I much prefer just listening to my Sonos home audio system which sounds even better with my new hearing aids (and which I believe will still be improved with further adjustment).


It is possible to do what you want, with relatively newer ReSound models, a newer vehicle designed and configured correctly to work with iPhone, and a relatively newer iPhone. Your hardware doesn’t have to be state-of-the-art, but you probably can’t do what you want with gear or a vehicle that’s more than say five or six years old. But as others have indicated, there’s a lot of variation even with newer gear that says it’s Bluetooth-compatible. It may work. It may not. If just one of the three pieces of gear was not made around the same time as the others, your chances for difficulty increase.

For example my iPhone 6 and my ReSound LiNX 2 aids work as you’re seeking in my 2016 Toyota Tacoma and 2017 Jeep Wrangler. All these were made within a couple of years of each other.

However the iPhone only works in the Jeep if I am set as the primary Bluetooth profile in the vehicle. If my wife is set as primary and I’m set as secondary, my phone doesn’t work as you want if her phone is in or near the vehicle. Also my iPhone can play music via Bluetooth through the Tacoma, no problem, but through the Jeep, I have to do this controlling the phone manually. When the truck is running and I step in, it can be set to start playing music from the phone automatically and does a great job. Not in the Jeep. All this stuff is very twitchy and can require trial-and-error, and I wouldn’t expect an audiologist to be able to set this up for you without extra fees.

Also be aware that Bluetooth is a significant security risk. Your vehicle or your phone, probably your aids too (though I don’t know why anyone would bother), can be hacked by an expert bad actor nearby, say one lane away, without a lot of trouble if Bluetooth is enabled.

1 Like

My iPhone is set for the car, if I wear my compilot it’s set for my L ear and my Phonak. It’s also set for my CI, and all 3 together its jolly confusing. So I don’t wear the compilot anymore. Even so if I’m in the car, the car overrides all of the above and automatically answers the phone. I don’t mind this as I can now hear and answer the phone hands free while driving.

1 Like

I’m just back from the audiologist for a fine-tuning of things. I mentioned this issue and was told there’s a setting in the IPhone that will turn off the transmission of GPS directions to my ears and leave it with the phone speaker. I’ve opted to leave things where they are at the moment as there is some chance I’ll swap out the rechargeable OPN 1s for the battery version. I hear fine, but the width of the rechargeable one is fractionally uncomfortable when combined with the earpieces of my glasses. It’s always something!

I have set audio routing to be always hearing devices so all audio including when connected to my car (This includes CarPlay) is directly streamed to my hearing aids.

I have Bernafon Viron HAs, an iPhone SE and a Citroen C4 Cactus. The media streaming is set to automatic but I think I did have to tell it to play through the car the first time, but since then it plays music and phone calls through the car and if I’m not in the car it streams everything to my aids

Oh, no actually I remember now, I had to tell it to play through “dock” when I plugged in via the lightning cable. All the bluetooth automatically went to the car

iPhone X, 2018 Subaru Crosstrek, and Resound Preza’s … everything on my iPhone, including Siri, music, Messages, and mapping goes straight to the Subie when plugged into USB and using Apple CarPlay. If I don’t plug in, the iPhone connects via Bluetooth and does phone calls and music to the car, but not other apps like mapping and Messages. The Lightning USB connection is faster and more solid than Bluetooth.

Hi ToriNi
Just seen your post regarding car connection and you stated that sound from CarPlay comes to your aids but I am having trouble with getting sav nav directions to my aids although I have call audio routing set to use aids and even when I go to AirPlay in control panel my phonak aids are ticked.


I did try this with Waze through CarPlay and it did stream into my hearing aids directly but usually have the directions on mute so haven’t tried this recently. Not sure why it wouldn’t work for you? Try Waze as it works with Spotify directly and it stops the music to state the directions and then continues to play the music.

But since the iOS 13 update, I have had issues with the connection as it isn’t automatically streaming directly to my hearing devices anymore. It did with iOS 12. I now have to manually switch to my hearing devices for it to work. It will however switch automatically for calls though. Not a biggie but just annoying.