hi, i've just done a diy aux-in for my pioneer hu that supports aux-in. If you don't want to buy the aux-in cable from pioneer, this is what you can do. thought i'll share it with you all ;) enjoy
http://tzywen.com/modules.php?name=News&file=article&sid=155
http://tzywen.com/modules.php?name=News&file=article&sid=155