problems with some back ups
 

Hi there,
I've got some problems with my Ps2 back ups.
Some of them are working perfect and other ones are just giving a grey screen on my TV.
For exemple
SSX snowboard from big sports
Street basket
Surfing H30
and Star wars super bombad racing
I'm using a plexwriter24/10/40
toshiba DVD player
and CLONE CD
Can somebody tell me what I'm doing wrong??