Audio Systems: SOUND CUT OFF, fiberoptic cable, fiber optic cables

Question
My ML 500 '02 model sound system cuts off when ever its turned off, it comes up again if i plug out and plug in the fiber optic cable in the head unit and the CD changer, it then goes off each time i turn on and off the unit. Right now the unit does not dectect the cd changer anymore. Do you think i shoud change the fiber optic cables for the stereo, Amplifier and Cd? can anyone also recommend where best to buy these cable and with a tel. No.
Thank you

Answer
Mercedes fiberoptic cable is very expensive it is better to buy just any regular fiberoptic cable by the feed and make what you need

if you bend this cable a litle to much and it will get damage
most of the times we find the damage on the floor rear seat near the door or near the amplifier in the  lef fender

do this remove the radio and get a regular flash light,put on the cable and go in the trunk unplug the cd changer you must see the light if not unplug the amplifier and see if the light is there

if the light is there about 10 inches from the cd changer there is a way to remove the cd changer cable and close the loop

sometimes the cd changer goes bad and you lose audio
unplugin the cd hcanger don't help and there will be no audio
the cable needs to be remove  

good luck