I don't think a reinstall does anything to your preferences... and a corrupt preferences file may cause problems
Reset Corrupted Preferences = Press/HOLD Ctrl+Alt+Shift while starting program
-except delete file in P6 http://forums.adobe.com/message/4644893
-and setting http://forums.adobe.com/thread/1058426?tstart=0
I think the above is for Windows... I don't do Mac, so have NO idea if the steps are the same