Today I have checked my stock radio and see that the radio has a cd changer connection! If you look on the back side of the unit you can see a yellow plug. Removed it and see the D2B connection for a CD changer. I know that D2B form my Mercedes Benz E-Class and I'm very safe that the unit will work with a cd changer that has D2B together! Also I have seen that you can connect an analog cd changer too. You see the big black plug with all wires and over there is a connection that my old Becker radio uses for analog CD changers!! I hope that help all of you.