can't read double layer dvd anymore

I have 2 amd64 installs and all was good until a few weeks ago I don't know the exact date.. But I can't use the double layer Suse dvd... When I browse it appears to show the contents but I can copy files off of the dvd I just get a i/o error. These are 2 different machines and using 3 different drives that all worked before.. If I boot from the suse dvd all is good I can copy and read the files -- Ray