Clio 2007 Mk3 AUX and USB issue

I've just bought a Clio 2007 mk3 and in the glove box it has:



I plugged a standard AUX wire into the AUX port and then into my iPhone. I enabled AUX on the head unit too. I then switched to the AUX mode and then tried to play some music from the phone but to no avail. It has this head unit: