Hi, I recently purchased a 2015 ford KA, and been trying to setup the aux/bluetooth to play music through spotify. I first noticed there was no aux input and it was USB instead. So I bought a aux adapter as long as a normal aux cable, however I'm not getting any music being played as well as I keep on getting NO SRC pop up on the screen. Is there any way to fix no SCR coming up/ the aux working?

It's been a while since I had the original head unit but as far as I'm aware the USB source mode on the Ka only allows you to play music either from an iPod (the old ones like the nano, shuffle etc) or a usb dongle that has mp3 files on it. Bluetooth on the Ka only allows you to take calls as it doesn't support a2dp (The bluetooth protocol that lets you play music) there is an app on android that lets you route audio through bluetooth call mode but the quality is that of a call so not very good.

I ditched the original head unit entirely when I realised it didn't support bluetooth audio, the headunit uses a 1 din slot which is universal and you just need a replacement face plate to allow you to use an aftermarket head unit, if you go down this route and want the head unit to turn itself off with the ignition and support on wheel controls you will need a canbus interface as well.

Sorry this probably isn't what you wanted to hear, the Ka just unfortunately has a pretty crap head unit.