sniper Modchip doesn't work with GAP-Bios!

[Murks83]

I can play normal PS and PS2 games and DVDs (Videos) but when I insert my CD with a DVD-Rip there are many things that happen but it doesn't work!
These different things happen:
1.Sometimes the PS2 reads the CD and then a blank screen remains.
2.The PS2 boots till the Playstation2 logo and then a blank screen remains.
3.The doesn't boot, there's only the PS2 Main-Menu appearing on the screen.
4.The PS2 tries to boot the CD but then it recognizes that there is no valid PS /PS2 DVD/CD in the PS2 drive

When trying to read the CD there's also coming a big noise from the PS2 drive, I only knew from my PC-CD Rom drive. But that sound only occurs when I insert my DVD-Rip CDs!
What is it all about?