Did you check the checksums of your BINs on redump.org?
Disc 1:
http://redump.org/disc/655/
Disc 2:
http://redump.org/disc/656/
I've got Valkyrie Profile, and I can verify that the checksums they have are correct since my discs are basically mint.
I haven't played it on a PS2 though. It's been years since I've played it, and I only recently repurchased it (original was stolen . . . :().
I'd test it for you, but I'm not going to be at home for the next two months.
I can look into it in August when I get back.
Hope this helps! ;)