V12 - When I put in a DVD the PS2 turns off. What to do?

Hi

I have a PSTwo V12 with a DMS4 Lite and a V12 fix installed. After a while (6 months) it came back and when I now put in a DVD to the console it turns off itself? :S

I have picture and sound but as I said, as soon as I put it a DVD the laser moves to its readposition and then turns off itself. No reading at all.

Please help
Thanks

Yeah, it do that a lot. Hope some one knows the answer soon.

does it do this with backups and originals? can you disable the chip and try an original?