Hi Arrow, I am struck with the same write problem. I can't even get 6x to work on my 755A. The first write is ok, the second one poor and after that, it is russian roulette if the disc will ever erase again. I just lost another W21 that way. Just to make sure, I stuck a very poorly burned disk (pie up to 1500) into a GSA-4167B and rewrote it 8x (without prior format) with very neat result. So it is not the media. This is really bothersome. The king of quality eats away my disks! I wish there was usable media. But I know of no working alternative.