PS2 backups boot but freeze during gameplay

[gaggil]

I have a modchip.com modchip and a gameshark V1.3

PSX backups, PSX originals and PS2 originals work fine.

PS2 backups boot up fine and function until I attempt to start the game. It goes to a black screen and stays there.

I have had this problem with Winback, and Star Wars Starfighter.

I have burnt the games using Winoncd, Fireburner and Cdrwin with the same results.

I am using Memorex Cdrs

Any help would be appreciated.