New to real-time myself, so take this advice with a pinch of salt....
Have a look at the options under Tools (menu)>Options (menuitem)>RealTime(tab). Try unchecking the recalculate expert, and change the commentary settings.
wabbit :D
The MS Bible:
Recalculate Expert Live. Check this box if you would like the experts that are attached to your intraday charts to recalculate and update with each new tick. If left unchecked, experts will only recalculate at the completion of each bar. A mathematically complex expert can be demanding on your system's resources, particularly with actively traded securities. If your system is struggling to keep up, you may want to leave this box unchecked.
Update Commentary on. Choose when to update the expert commentary attached to a chart—with each tick, at the completion of each bar, or with the Refresh button only.
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