Burning Speed problem

I seem to be having a problem with my lite-on dvdrw shm-165h6s. When I first installed this burner it worked perfect, then all the sudden the burn speed slowed tremendously. It was burning DVD’s in 7 min. now it takes almost an hour. Can someone Please Help me!

Check that DMA is enabled & that the drive is running in Ultra DMa mode 4. Try this link