How can I fix this problem?

I have a B&O 9000 (six disks behind a glass door) system which I have had for about three years with not much use.

When I choose any CD the arm will move to the CD which sometimes starts spinning and playing music then stops and displays PAUSE. On occasions when I select the CD it will go straight to that CD and then display PAUSE.

I have otherwise had no issues with the system.

I have a children's birthday party on Sunday and was hoping to use the system.

Regards,

Paul