CD63 occassional radial error

Hi, ive taken a search through the forum, however, cant find anything matching my problem.

I have a marantz recently purchased used that is fine on majority of cd's except 2 Pink Floyd cd's !!! (now you see why i need help quickly lol) It will play occassionally if i put in and out, cant say for sure if its position in tray or temperature ?

A check through the service facility shows a Err10 (radial error) on this particular cd, the copy of this cd(although i'd never admit to it!) plays fine.

The laser pick up, tray and cd have been cleaned with a cotton bud & IPA solution, dried and blown clean with an air duster. another cd that was a problem is now solved. All CDR's are ok, other cd's are ok.

Whats the problem, what is exactly the radial error, is it the cd itself or the drive ?? I read that years ago some cd's varied in quality and errors, is it possible i have nothing to worry about ??

Your advice is extremely welcome.

Thanks
Dennis