No audio using front earphone jack

Hi,

Just completed building a new computer. Parts purchase online
including a Cd-r (brown box). There is no audio using the front
earphone jack on the Cd-r. However, there is audio when i insert the
headphone into the on-board jack at the back of the computer (green
color jack).
I also have connected the 3-wired 4-connector cable from the
motherboard to the cd drive.

Thanks in advance.

TPJOE