LITEON DVD scratching

I’ve noticed circular scratch on some of my CD’s and DVD’s. It’s 1.5 cm from the inner hole and is about 3 mm thick. My DVD drive: LITE-ON DVDRW LDW-811S, firmware: VHS0R. I highly doubt this is because of some rubbish in DVD drive. Have anyone encountered similar problems? Could anyone provide possible solution?
Sorry for terrible English

Which media are you using?

Acme, Verbatim etc.

Is my question serious, maybe it shouldn’t be in newbies forum? I’ve found one topic called “Can a laser make contact and scratch a disk”. Is it possible or should I look for some rubbish in my drive? The disk is scratched a little bit everytime I put it into DVD-ROM, however I hear no sounds. DVD drive still works fine.

Definately sounds like a hardware issue… Have you tried spraying compressed air into it and seeing if the scratch moves or goes away. Does the scratch stay in the same place all of the time, or does it move in and out?

Yes, I’ve tried spraying compressed air. The scratch stays in the same place all the time, but it’s not always the same intensity. It seems that some part of DVD-ROM contacts disks itself.