Unit can be bought from here (click).
First of all need to take off main MMI component & air climate panel.
To pull off this unit, you’ll need VW radio removal tools.
Insert VW removal tools inside the two holes in each side of MMI unit.
You will hear a “click” noise, then you can pull off whole unit. After that disconnect all cables from unit.
Now we need to make few changes to have a sound coming from CarPlay to MMI (the hardest part – we recommend to do this via advanced installers).
NOTE!! THIS IS ONLY FOR AUDI Q3 OWNERS!! IN A6 / A1 DO NOT NEED DOING THIS!!! YOU ONLY NEED TO HAVE AUX
After that, you need take off climate control panel as will need put cable spliter there.
The best way to remove it, is using trim removal tools on each side:
and pull it off.
Another step is to connect all cables like on this diagram
and the last one is to check if everything works fine!