[header] How to remove a stuck cd from a kenwood kdc 138 cd changer [title] Try to locate the reset button on the face of the unit. [step] It will likely look like a small hole. When you find it, use a straightened paperclip or toothpick to insert into the reset hole and press. 
This will reset all your radio settings and your clock to 12:00, but it should cause the unit to eject your cd (s) when you press the eject button. [title] If the above method doesn't work, you'll need a q-tip with a sturdy handle.