usb and aux not working bmw x5

[ksnegi]

hi ,

I have a bmw x5 e70 MY:2007 in the center arm rest I have a usb port and aux port. when I connected my iphone 4s and iphone 5 to the aux port music didn't play. so I bought the bmw y cable from the bmw dealer and connected it to my iphone 4s, but still the music is not playing or can I see the songs of my iphone on the idrive screen. the iphone 4s says "iphone accessory connected" when I tap the music icon so I also cant choose music on my iphone. when I remove the usb extension of the bmw y cable from the usb port in the center arm rest this screen on my iphone goes away. I also tried connecting a usb stick in the center armrest but on the I drive screen I cant see anything happening I go the aux screen but I cant see my music and the music doesn't play. But the usb port does charge my iphone 5 or 4s when connected.

I hope you can help me.
thanks in regards,

Negi