Poor performance with the nav map

[Paul Riley]

One thing I have been concerned about lately is the poor performance experienced with the nav map,especially when zoomed in closer than about 1250km,where at 50m scale the map is practically unmovable,a serious problem when trying to plot a vessel's speed.I noticed this problem seemed to start as my campaign progressed,because early on the map was much faster at 50m scale.
Is this all due to higher traffic in the seas as the war progresses?,I seem to think it is.
My only solution at the minute is to try and take speed plots at 1250km scale,increasing the margin for error,but it doesnt seem too bad so far.
As far as system performance goes,I have a decent AGP card with the latest catalyst drivers,regularly perform daily maintenance on my system (clean all TEMP files etc),regularly defrag my HD...and so on.
I also disable virtual memory also,as I have enough RAM installed,and RAM is faster than virtual RAM,by a long way.
So,if anybody else has experienced this serious annoyance could they advise me on how to deal with it?.

Thanks