InDesign CS5 File Saving Options

Whenever I select "Save As" from the FILE dropdown the name of the file is highlighted automatically.

When using the keyboard to browse for the location where I want to save the file, anything I type is typed in to the file name box and the file name is changed to whatever I may have typed while browsing. Most often I have already named the file and may simply add a revision number or reference.

I do not want to change the file name completely and would rather not have to retype it each time.

It is extremely frustrating to have InDesign automatically start changing the file name as a result of browsing for the save to location.

Does anyone know how to stop this? Seems like I need to stop the highlighting of the file name box when I select "save as" .

Many thanks!