I suppose this happens to you in the layout editor.
Could it be that the object is 'BIG' and on top in the Z-order ?
Could it be that you have snap on grid enabled?
Then you have problems selecting the other objects, and when you drag it snaps to the grid.
This is a wild guess, not the case, plz upload a capx.
If thats the case: Change the Z-order, so that object goes to the background of the layer. Or bring it to its own layer an lock that layer.