It seems counter intuitive at first, but I think the centrifugal force due to the high rotation speed of the disc helps to flatten it out a bit. Ellis On Thu, Nov 7, 2013 at 6:20 AM, Tom Fine <[log in to unmask]>wrote: Once they get un-flat enough, they are hard for many players to reliably > read at 1x speed, but seem to be OK to rip in my Plextor PC drive. >