Sony PCV-RX850 - Manual (Page 89)

Why doesn't my optical drive (DVD-RW) record to CD-RW media at higher speeds?
If you are having difficulty formatting CD-RW media for recording purposes, try changing the write speed to a lower setting.
Your media must support writing speeds at 2X or lower.
See the Help or documentation that came with your CD or DVD recording software application for details on adjusting the
write speed settings.
Your DVD-RW drive does not support high-speed writing to a CD-RW media. Verify that your CD-RW media supports
writing speeds of 2X or lower.
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