Sony Optiarc 5280s CB Plus: Any way to change media burn speeds?

I utilize the overburn feature on this drive to burn XGD3 games (8.13 gb) and I have been using TDK discs with great success. Until recently the discs arrived with media code CMC MAG-D03-64 and these discs have all resulted in failed burns. I have tried burning at 4x, 6x, and 8x. It will not allow me to select a slower burn speed than 4 and all I have are coasters from attempting these burns.

I have also tried both 1.z7 and 1.z8 firmware and the results are the same. Before, my results were great using TDK discs but those discs always had the media ID of Ritek-S04-66.

I bought a pack of Verbatims and my results are stellar, the only problem is that they only allow me to burn at 2.4x speed. Is there any way to speed it up? I remember Liteon drives had an overspeed option in IMGBurn that would allow these discs to burn at 4x or 8x speed.