Linn Classik Movie, dvd problem


my Classik Movie shows "no disc/unknown" ,after I insert a dvd.
I do hear that the Classik movie is trying to read the dvd a few times ,with no result.
With music cd`s ,the Classik Movie works perfect however!!
Does somebody knows what the problem can be?
Did you clean the lens?
Not yet, but if the lens is dirty why does it takes music cd`s?
Well, I cleaned the lens , dvd`s work again!
Thanks bday!
You bet, Ctchen! Rock on!