How do I get my B&O 9000 CDs to play smoothly?

I have reset up my 9000 system after 3 yrs on a closet shelf. The CDs turn but there is a faint metallic sound as if they are rubbing somewhere .In some cases the CD sticks and the player stops and returns to the start position. Is this simply a "settling in" issue and can be fixed with lubrication? or more serious. Thank you in advance. All other features are working.