Problem with disk and console

[Yuffie514]

I have this original ff8 ps1-game and ps2-console. When I put the first disk to teh console, it just does something or should I say nothing and then it infoms that error reading disk. There´s no obvious marks or lines which might do errors. I just bought it and it´s used. All disks seems ok, but console just can´t read it. What might cause this? The disk is also clean.

is that the first time it happened ? maybe you already know this stuff , but my console will also do that to me if a disk is dusty or it's not in the center of the tray .