How can I fix my radio?

I have a fiesta 2007 which has a CD 6000 radio and CD. The radio works OK when the car is stationary but as soon as I move off it goes dead and will not come on again. I believe the car was immobilised for quite a while by the previous owner due to ill health. (don't know if that has anything to do with it) The CD is not affected and will play when the car is moving.