Audio Systems: 2004 X-type No Sound, optic fibre, stearing wheel

Question
Hi I have a X-type (2004) with no sound, the radio appears to be functioning correctly ie radio finds stations, cd display track info etc. But there is no sound from the speakers. I have checked the optic fibre with a torch and there is 12V at the amp. I think it may be some comms fault as the cd changer button doesn't work either (the stearing wheel buttons do function and the cd changer will eject the magazine, so power must be there also). Is the comms done over the optic? Any help would be appreciated.

Answer
defective cd change, remove it  couple of inches from the cd changer there is a connection open the clips and remove the cd changer cable plug the fiberoptic back ( close the loop ) and the radio will work again
good luck
you need a new changer