I have a text box that sits outside of the main shape, it's recently started jumping around. When I double click to edit the text the text positions itself correctly and stays there. The same happens if I just open the shape sheet. It's almost like it's applying a margin that disapears when you open the shapesheet/select the shape.

Has anybody come across this before, it's driving me crazy, can't see any of the obvious values changing.

which version of visio ?
can you attach your problem file in vsd format ?