If you're referring the the PX-708A that is the factory read rate. Plextor offers a SpeedRead option in all their DVD burners which can be enabled by holding the eject button for three seconds before you slap a disc in
so your drive wasnt locked to 2x for movies to begin with?? unlike quite a few manufactures I know my old hp will never read movies over 2x, my sony wont either, the pioneer is unlocked and averages around 8x read and the aopen rom is around the same