Hi. I have a V12 (slim) ps2 with the mx4 modchip. However, it wont read backup cds at all, or with great difficulty. The unit vibrates like hell, as the cd spins the drive tries to read it. The same cds read perfectly on my older v9 with the matrix infinity chip. What could be the problem? Bad chip installation, laser problem, or doesnt the v12 like cds? Thanks.