Try Changing your DMA setting to PIO via the Device Manager for IDE Channel of your Burner. Also it's recommended to install it as a Primary Device on the Secondary IDE channel.
Also try upgrading the firmware. http:
www.pioneer-eur.com for official firmware. Below is hacked firmware to allow the drive to be Multi region DVD and burn any disc @2x speed.
http://81.97.231.148/pioneer2x4all