Never use a burner to do media integrity checks. Always use a CD-ROM. And I'd rather trust dedicated forensics tools like CD/DVD Inspector, and not semifunctional gimmicks like CD-Speed.
Surely enough Inspector is not a saint (the device driver it uses is very obtrusive), but if you activate it just every time you want to scan a CD, it gives really reliable results. Actually if you follow the Inspector online manual you will se why the diagnostics should be performed on a CD-ROM, and not the burner.
Of course there are also some other very good diagnostic tools, but mr. Deppe's CD-Speed feels and looks as dubious as other Nero goodies. Actually you already have a good idea about it by your own experience.
The revolution cannot be a lever, or an essay, or tablaeu, or embroidery. It cannot proceed mellowly, piece-by-piece, gently, devoutly, simply and humbly.
Mao Zedong