I think you might be trying to burn too slowly. The Taiyo Yuden T03 are a quality 16x disk. Don't burn these at 4x , try 12x & the problem might go away.
Also for the other burn at the rated speed of the media.
You could try updating to A106 firmware, although I doubt it would change things.
Finally update
Nero to 6.6.0.18 (if you can find it) or 6.6.1.4.