The iPhone headsetfrom Apple can work with Elgato Thunderbolt™ 2 Dockas basic headphones.
The iPhone headsethas a few special features that will not work with Elgato Thunderbolt™ 2 Dock.
Headphone Jack of Elgato Thunderbolt™ 2 Dock
You can use the iPhone headsetas headphones, if you connect it to the headphone jack of Elgato Thunderbolt™ 2 Dock.
You cannot use the transport buttons (move forward, move back, pause) or volume buttons.
Microphone Jack of Elgato Thunderbolt™ 2 Dock
You cannot use the iPhone headsetas a microphone.
If you connect it to the microphone jack of Elgato Thunderbolt™ 2 Dockthen it won't work at all, as headphones or a microphone.