Confusing isn't it!

Take this one for example. As I understand it, any unit that has two 'bus' ports on the back and a 'mode' button on the front instead of a 'CD' button should be aux compatible. This one has both but only has one antenna port as far as I can tell. In fact I haven't seen any yet with more than one antenna port including the older cassette ones. Am I looking at the right connector?

BMW BUSINESS CD PLAYER E46 (3-SERIES) on eBay (end time 11-Nov-10 09:11:33 GMT)