Red Screen with Backups?

[parkerdog]

I have a modified playstation that plays backups without a problem. I recently purchased a premodified 39001 V7 magic2. It plays all original PS, PS2 and DVDs without a problem, but when I try a backup I get a red screen telling me to insert a PS or PS2 Format game. The backups still work on the modified PS and I tried burning a PS2 with CloneCD and using it in the new PS2. I still got the red screen. Any ideas, right now I basically own a regular PS2 that I paid a lot more money for.