Hi Kevin,
Thank you!
Worrying that it seems to be my computer/settings rather then my file but that might help get to the bottom of things,
it looks like it was the section viewports for me.
to workaround I had to convert both the section viewports to groups and put my annotations for them in another scaled viewport not showing any other layers...
One thing I've noticed is that things will slowdown if my viewports need updating and my viewports always need an update if ive gone in to edit an annotation. I dont remember this being the case with vw2012 (the last version im familiar with!)