you need to remove the top off the dvd case should be 2 screws at top front & 2 side clips at the back easily opened with a flat screw driver.
then you need to get a cotton wool bud with some cd disk cleaning fluid and give the laser a good old clean first wet then dry end of cotton wool bud 9/10 this is usually the problem dirty old laser,but worse off the laser is knackered and needs replacing.
but if you remove the laser unit you will see 2 pots underneath 1 saying cd the other dvd,find out which disk work ie cd or dvd 1s and turn the pot clockwise just a taj & I mean a taj but thats the real dyer last resort & make sure you mark the 2 top clogs before removing the laser so you can line them up when putting back together.
hope this help out
Guestie
Stephen Guest, February 2008