One of the engineers in my office is having a problem where, whenever he edits text with the in-place text editor, any input causes the view to "jump" away from the text (and zoom in considerably). No matter where he is or how he's zoomed in the drawing, two keystrokes or mouse clicks while the in-place editor is open will send his view well away from the working area where his drawing is.
He tells me that he didn't change anything (except maybe getting a new monitor?), and I've confirmed that this happens on any text in any drawing, including drawings that he was working on successfully just yesterday. For now, I've bandaged it by using "oldeditor," but he doesn't like it and would prefer to get the in-place editor working again asap.
I have seen similar behavior to this. It happened to be the mouse scroll button being messed up. You can try updating mouse drivers or changing AutoCAD's zoomfactor setting. You might just want to swap for another mouse and see if that's the problem.