Can't Boot DVDR Backups. please help

[donutboy31]

i have a swap trick modchip on my ps2. i beleive it is a neo 2.2 or 2.5. I cannot bot any dvdr backups but i am able to boot up cdr backups. the sound usuallly goes like this..

it reads then goes da than da 2wice

now it goes da than starts to click for like 4 seconds then re-reads it again.

This happends during the part were u already inserted the dvdr origional and haver place the backup dvdr.please help