Concert stereo problems

For the last couple of months my concert stereo single disc player has been playing up , occasionally the sound would go off ,everything on the stereo works but no sound comes out , leave it a few minutes and all is well ,it is then ok for maybe a month ,
yesterday though i noticed the front speakers were off , radio works fine but only from the rear, when fader is put to front nothing is heard
I have removed the radio checked all pins and connecters all is ok,
It is a 2005 sporttback sport model with no BOSE if that helps with no changer fitted.
Has anyone had this or is it my head unit ********

cheers mark

hi brian, cheers for that , mine doesnt go off, everything works as it should but no sound comes out of the rear speakers, thats the biggest issue now,the display is still lit as it should but just no sound from the front speakers cheers mark

Dont suppose anyone has a spare concert head unit kicking around if mine turns out faulty ? Let me know how much cheers mark