most likely DMA is disabled. with DMA deactivated the cpu has to deal directly with all inputs or outputs this takes a lot out of it mostly because it has to respond instantly giving the burner full priority. with DMA enabled things r managed with less cpu usage and more indipendanly. this applys specificaly when reading. i had to do a firmware update of my recorder to improve performsance and speedi suggest u dothe same. for me it also automatically enabled DMA or this can be done manually in the DVd-RWs properties.