I've been using the plextor 708a and it usually took 20-30 min to read a dvd and 15 min to write. Now it takes a hr and 45 min-2hrs to read and a hr to write. It started after I downloaded morpheus. Morpheus has since been uninstalled but nothing changed. Could it be the driver has had its time. Its about 2yrs old.
Is the drive still in DMA transfer mode? Here's a link to check: http://www.microsoft.com/whdc/device/storage/IDE-DMA.mspx
Go to device manager / ide ata/atapi controllers / primary or secondary channel and then rightclick ,properties then advanced settings. If transfer mode is pio change it.If it wont let you uninstall the channel your drive is on and reboot,your computer will reinstall the driver and will be on dma