my car was originally equipped with cd changer. someone had removed the changer when I bought the car. i got used x5 changer few years back and decided to install it now. all went fine, two plugs into the changer and it came to life. the problem is, menu shows no cd-s but there are cd-s inside the changer. original music cd-s, not homemade stuff. any ideas what could be wrong? there is also one round socket on the changer that reminds antenna connection but i could not find any suitable wire for this one. could this be the problem?