I just installed a Blaupunkt Melbourne sd27.I clipped the A2 phone wire as was directed by info on this forum.The radio plays but when I put the sd card in and push the src button the display reads cdc/aux then it flashes check aux and then it reads aux.I do not have anything plugged into the aux in the front or the back.It does not display sd card and does not play the music on the card. Is there anyone who can help? Thank you.