Hi again!
The solution to my problem as described in first post,
was a to slow a computer, so no blame should fall on Steinberg or Yamaha for this.
BUT, the computer i tried it with was a Asus with C2D 3.0 GHz and WDC disc, win7 and 4gigs of ram.
I personally think that should do the job, but no.
I switched to a Asus with an Intel I7 and WDC disc win7 and 8gigs of ram, and now the playback functions brilliant.
So my advice to future users of CL3 and Nuendo live is: Overshoot the system demands as much as you can, and everybody will be happy!
Cheers…Its friday