Play stops repeatedly when zoomed in a lot

Hmmm...

This one I repeatedly did in both X3e as well as SPlat...

I have a complex song with all tracks frozen... I have recorded a vocal track with 15 Lanes.

Whike comping I had need to zoom to a point where roughly one measure filled the screen time wise with all tracks shining and the vocal track showing the Lanes...

All was well up until then but when zoomed in, Sonar would drop out of play within a few measures and be sluggish to respond to controls. Returning to a zoom of say, 8 measures on screen and all is well again...

I was able to do this repeatedly going back and forth between X3e ans SPlat...

My machine has plenty of power... Dual Xeon quad cores and 16GB RAM... Large amount of graphic memory nought I forgot how much on a high end card that supports 3 dvi monitors though I'm only using one... My latency was at 3ms then raised to 5 and lastly to 11 with no change.

Even at the smallest latency my cores don't show much movement at all. Barely registering activity on each of the 8 cores...
This is a MacPro running win7 pro under Bootcamp...

Any thoughts about this? Suggestions? (Serious ones that is ;-))

Thanks Gang!
Keni

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