Mod chip question

[AdamR]

Hi all,
I have a few questions that i hope you can help with.
I just bought a PS2(new) w/ a mod chip & GS2 ver. 1.9(USA, I dont know the mod chip maker)

1- When i try to play certain games they fail to load sometimes on the first try, or after the intro movie they dont load any further. (Is normal? when using a MOD Chip and CDR's)

2- Also the drive spins up and down when loading and the head seems move like crazy when loading.(Is this normal when playing CDR's )

I was just wondering I'm afraid that the MOd chip is defective or not installed correctly or that the PS2 is defective.