Problem when launching a copy

[DSlay]

I've had this problem with few new games.

When starting the game, it goes well to the section where it goes black and then text "Playstation2 Infinity 1.54" reads. When the screen goes black again, ps2 reads the disc and then goes back to browser where it shows memory card and a disc which says "Playstation 2 disc"

Has anyone experienced thesekind of problems before?
Following games does this: SDvs.RAW2k6, Shadows of the Colossum, Newest DBZ (Tencachi or something). I also burned Worms4 to the same dvd's and it works without problems.

[spedmetal]

What version is your PS2? It sounds to me like you have a worn laser.

[DSlay]

It's v7, I doubted the laser too but I don't see the reason why other games (burned to same dvd's) read well, I've cleaned a bit the laser with CO² (some pressure air bottle it was)

(EDIT: I think it was the laser. I don't know what the hell happened but while I was writing the reply, the game started. I'll try cleaning up the laser or replace it with a new one later -Slay)

[ronetoneps2]

clean with alcohol

[Bartelbee]

i have a ps2 v4 with M.I installed 1.5 firmware and when i try to run a backed up dvd it just cant read the disc. sometimes it will read the ridata dvd -r but will skip and sounds like its spinning really uneven. I tried cleaning and adjusting the laser with no luck. The laser reads all original ps1 and ps2 games even the blue ones and will read any cd -r anyone know what could be going on? <i have tried a large variety of dvd - r>

[Bartelbee]

ps i get no error messages what so ever, just hear the disc spinning and the tv says "reading disc"