Symptom
The computer does not write CD-R discs at the maximum speed, even though the discs are labeled as being capable of writing at higher speeds.
Solution
Use CD-R discs that are capable of writing at 16x speed. The 16x or maximum option should be selected, if available, prior to inserting a blank disc. If so, the Combo drive is behaving correctly.
Combo drives included with iBook and PowerBook computers can detect imbalances in the disc that are caused by poor production quality or the presence of labels and ink on the disc's surface. These imbalances can cause write errors. When blank discs are initialized, if imbalances are detected the writing speed is slowed to between 4x and 8x write speeds (depending on the magnitude of the imbalance) in order to reduce the potential for write errors.