The other thing that can be an issue is the brand of media you are using. Perhaps it's of low quality?
Hi Cynthia,
Thanks for your help. Here's the missing line, no speeds :
I 19:47:20 Destination Media Type: CD-R (Disc ID: 97m26s11f)
Sure it's of low quality, this is noname CD-R, and this is one of the reason I would like to burn at low speed. With my previous CD-Writer (an old Samsung RW 52x), I was writing on these CD-R at 4x or 8x without any problem, and they were readable everywhere (in my car, on my PCs etc...). Now that I have a "modern" DVD Writer, I can't set the burning speed anymore ?