I have the same problem. I have a SOHW 1633s and the speed is slooowww.
Takes over 1/2 hour to read a dvd and 1/2 to a full hour to write the bloody thing.
The bios is set for UDMA 2.
"device manager, ide ata/atapi controller, and check in your primary and secondary channel. Make sure udma is enable, and not PIO mode"
On mine the transfer mode is set to "DMA if available" but still shows Current Transfer Mode as "PIO Mode".
It is not burning at once. I have tried several different burning programs.
I am new to this so please help me out guys.