That is not standardised across different headphone manufacturers and often doesn’t work. It doesn’t work at all on cars.
Analog protocols are not a good idea for this. Digital with a decent protocol is much more reliable, whether wired or not. In practice, the best option is either wired CarPlay/Auto or bluetooth.
Analog protocols are not a good idea for this. Digital with a decent protocol is much more reliable, whether wired or not. In practice, the best option is either wired CarPlay/Auto or bluetooth.