Dvd rom wont burn any more

:confused: please help, ihave been backing up dvds for ages now but all of a sudden it started to take a very long time to burn the dvd to dvd r.
I have tried loads of software, uninstalling etc then it stoped burning completely so i bought a new dvd rom and the same problem, formatted the hard drive same problem disk wiped the hard drive same problem, it seems to burn audio and data and copies dvds to the hard drive fine but just wont burn it goes through the process says enter blank media tries to burn for about 30 - 40 mins the says failed to burn.

Tried different media?

Yes, i have tried different media, 2 different cd roms reinstalling software and windows, and at least 4different brands of burning software.

Check your DMA settings

i have checked the dma settings and they are correct.