I have been seeing those same cd speed errors on my system , on my BenQ 1640 as well as my pioneer 110D. my cd speed is 4.9.3 then 4.10 I dont see errors when using normal burning program like nero 126.96.36.199 or imgburn from lightning.
I am thinking there has been something not right with the cd speed create data disc writer since about 4.04 if anyone would like to comment i would love to hear others thoughts on, the cd speed burning error messages.
Intel Core2 Quad Q6600 2.4Ghz Intel D975XBX2
Plextor 755SA 1.08
Samsung SH-S203B SB03