Default scaling bug

Photoshop is not remembering the default setting for scaling. It automatically reverts to non-proportional scaling, forcing me to take an extra step by clicking the "maintain aspect ratio" link button every time I need to scale an object, which is quite often. It matters not whether PS is continually open or restarted: It always reverts to non-proportional scaling as the default setting after each use. This has been occuring for several days now. Please fix!