This is because older versions of iDrive didn't have the correct chip in the combox. Hence the box in the y lead contains a chip and costs a lot. With new BMW iDrives and the new F56, the chip is built into the car. What basically happens is that if you put a y cable in an F56, it decodes the data twice, and will not work. Just use genuine USB socket, and it will work fine, as the chip is already built in. Trust me