mariosprob

hi . i am completely new to the forum.i have a honda jazz 06 with the aux input near the lighter...i took a small 3.5mm audio jack cable and connect it with my mp3 and my phone...automatically changed from cd to aux but nothing happened.i pushed the cd/aux button take it to aux nothing again.the screen says aux but nothing happens no sound .what i can do ?why this is happening ?and what i am supposed to connect in that port?