I have CD-R purchased on the market which marked speed=52x. The speed of my Samsung writer is 40x-12x-40x. However on burning it only indicated in the range of 20x-30x varying from disc to disc, I used following commands to burn;
# mkisofs -J -joliet-long -o cdimage.raw /path/to/files
# cdrecord -v -eject cdimage.rw
The cdimage created has no problem without any warning, also checked by mounting it as loop. Whether I did some thing wrong? OR the speed on the discs was over-marked. The discs were manufactures by the brand-name of multi-nation companies. I found this problem on many occasions.
Burning CD-RW has no problem of the same kind. The burning speed was the same as marked on the CD-RW disc up to 12x allowed by my writer.
Please advise. TIA