If you have already found yourself in a situation where the music you listen to in your AirPods suddenly starts to be broadcast via your car speakers when you start it, you are apparently not alone. Apple introduced a simple solution to the problem in iOS 26, as identified MacrumorsThis should also work with any other pair of wireless headphones connected to your iPhone.
Open the settings for your iPhone and access the General> Airplay and Continuity section. You will find an option “Store the audio with the headphones” that you can activate and which maintains audio reading via your wireless headphones even after your iPhone is connected to devices such as Bluetooth speakers or carplay compatible stereo channels.
Having the activated option does not permanently prevent you from listening to music or podcasts via the stereo channel of your car. You can listen to your vehicle’s stereo chain at any time using the iOS control center or the Carplay interface, and you will always have access to other Carplay features while your phone audio is transported to your headphones.