It worked before, but it doesn't now.
Hi ajcorp !
Defective Media is always a possibility, but have you tried cleaning the label side?
Especially clean the hub area.
The hub area contains marks which are used for Media Detection, Media Positioning, and Timing.
Media Detection is probably the touchiest of the three.
Also, try another disk. There is more in the "Knowledge Base" under the "LightScribe Toolbox" in the links at the top of every page.