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Hi,
Looks like you are using AutoCAD 2016 for Mac. In this version "TrueType Font Performance Improvement" was introduced.
In earlier releases of AutoCAD for Mac, a drawing containing a large amount of TrueType font text can cause slow performance or disappearance of text during panning and zooming operations. With this new feature TrueType font text are retained in the drawing and the performance when panning and zooming is considerably improved. But there is negative effect of this feature - "Jumping text".
The problem was partially solved with Update 2 and 3, but not fully.
You can turn off this feature by setting DTTEXT System variable to 0 (zero):
http://help.autodesk.com/view/ACDMAC/2016/ENU/index.html?guid=GUID-53797F7D-69CC-40DE-951A-13058AF6E...Maxim