Same issue i've come across had mate...... but mine ended up being a LOT more worse.
Chances are that the dvd region x is OLDER than the drivers on your ps2 (If you have a fairly new machine v7 then it is def)
Because the drivers are incompatible with the disk it simply messes it up. I used an old version of dvdregion x (not thinking) on a brandnew v7 machine. It messed the drivers up for EVERYTHING. it didn't know what a game was anymore.
As far as i know sony don't like sending the disks out.using the old disks as well are no use as they won't write over the other drivers.
I'm sorry i can't be of any use, i ended up taking the machine back.