Mdi not working

[Spoonz]

Hi all,

Brought a mdi lead. Plugged in my iPhone 6s and my iPod and neither are working. Am I Doing something wrong?
I couldn't add the pictures of the lead. It's 5NO 035 554 H, 1515A, VVL VW AG.
I have a sat nav version. I've read about updating the stereo could be the issue but I have no idea where to get the firmware or how to do it

[Paradox1]

I'm not sure why.

Mind didn't work straight away. I left it plugged in for a few minutes while driving then I saw the MDI pop up on the screen.