pioneer xc-l7 cd ?

I have a XC-L7 and have taken it apart to clean the lens - from the display it is now working prefectly apart from now I have no sound. Thinking I may have pulled a cable of inside I again dismantled it but can find nothing wrong.I have plugged in another hi-fi and the speakers work find - any ideas as to what I could have done wrong otherwise I will need to buy another - anyone know where I could get one?