setting level symbology overrides for reference files


I often set level symbology overrides (color=0, style=off, weight=0 for all levels) for attached reference files.  For some reference files, I can select all the levels, right click, and then set the symbology overrides in the "level properties" box.  This then sets the overrides for all the levels of the reference file at one time.  However, for other reference files, this procedure does not work...I have to set the overrides for each level (one at a time)...they wil not all change together at one time to the desired overrides that I set.  Does anyone have any suggestions?