Help! Nero 6,3,1,23 JustSpeed Option

Would appreciate if you could help:
I’m using TDK 52/32/52D CD-RW burner with Nero 6,3,1,23 & everything was working perfectly till a few days ago when an exclamated warnning message started appearing prior to writting stage, although it still burns. The message says something like: “Quality may be affected by not using Justspeed option” and the burning process was slowed tremendously. Please help!! Thanks. :confused: