DVD drive won't read back-up game DVD

[dustin_ds3000]

I have two DVD drivers, one is a HP DVD1260i Sata and the other is a HP DVD1070i Sata, The HP DVD1260i reads the original DVD and the back-Up game DVD just fine, while the HP DVD1070i only reads the original DVD. When i put the back-up DVD in the HP DVD1070i it sees it has a blank disk. I now the HP DVD1070i has read this back-up DVD before because i used it all the time before i got the newer HP DVD1260i. The game is The Elder Scrolls IV: Oblivion, and before someone comes in here and calls me a pirate, look at my games on steam, dustin_ds3000 games

Edit:

i just went through about 50 dvds, most of them was original DVD's and some was back-Up DVD's. All of the original DVD's worked just find and some of the back-Up DVD's work fine, the ones that didnt work were all Menorex brand.

Edit:

Taking the drive apart to clean it didn't help either.