Did you try a DVD lens cleaner? I always give that a try before I pay for repairs.
I have a samsung dvd recorder only 2 years old with hard drive. recently i have tried playing dvds on it but after 5 minutes a notice comes up stating the dvd cannot be played. i have tried other dvds only to have the same notice displayed. all of which play fine on other dvd players and which i have viewed on this dvd recorder previously. it makes a loud noise like an engine before this notice is displayed. any ideas?