Hi All,
First, Thanks for all your suggestions!
No, it was not TC, nor a virus, nor MP10, nor the display driver (even though I installed CAT 5.8, which didn't help).
The reason was a long line....When I started this mission, I plotted a line staight from Lorient to NY - and just left it there for reference. Deleting that line immediately solved all stutters, so now I'm happy again
Just goes to show that very often you wind up looking in the wrong place in these matters
Thanks again,
BRGDS
Sven