I have had the same problem, so i looked on the nero website to see if there was any info there and this is what i found:
Q) I get a power calibration error. What does this mean and how can I fix it?
A) Power Calibration is controlled by the recorder. Before any write operation, all recorders must do a 15 step power test to determine the optimum power for writing to the CD; this is called "Optimum Power Calibration"(OPC). And during the write, it continues to do this test to get the best write throughout the whole CD; this is called "Running Optimum Power Calibration" (ROPC). This whole process is controlled by the recorder, though initiated by programs such as Nero. There is an area on the inner part of the CD for the test and test data info to be stored. You can use this area up to 999 times.
So, when you receive the "Power Calibration Error" or "Power Calibration Area full" error message, then the cause will be either poor media, poor Power, or a defective Recorder.
1) A might enable the OPC on this medium
2) Try another brand of CDR or CDRW media.
3) Also try different power connectors, and for recorders, do not share power with other devices. It needs its own power connector. If this occurs with an External recorder, the power source in the chassis could be the cause. Take the recorder out of the external chassis, and connect it internal, as a test.
4) Try different configurations, such as taking the CDROM to the Primary IDE bus as Slave, and have only the recorder connected to the Secondary IDE bus as Master.
5) Send the recorder in for Service.
Here is the direct Link: http://www.nero.com/en/632181809668074.html#23
I Hope this helps,