Tony, have you upgraded the firmware on your burner? I also have an A03 and have upgraded it four times. The first time was when it wouldn't recognize a blank DVD-R, and the upgrade did the trick. Subsequent firmware updates added support for higher speed media, and there was a mandatory upgrade to prevent overheating with higher speed media, if I recall corretly.
A03 firmware updates can be found here:
http://www.pioneerelectronics.com/Pioneer/CDA/ServiceAndSupport/SelfHelpFor...
BTW, to keep this post on-topic :-), I also create a folder from DVDWS and burn from there using Prassi Primo DVD. This has another advantage in that you can preview the production in a software DVD player before final burn.
----
Cheers,
Fred Scheifele
http://www.Scheif.net