You probably missed a spot for the fix. The patch did not undo mine.
check out http://geekmontage.com/texts/fallout-new-vegas-game-fixes-crashes-audio-issues-lag-saving/. the section on the mouse issue lists all 4 locations you have to make the changes.
Cloud sync we know is broken and it keeps a backup of the fallout_default.ini file that steam keeps restoring and overwriting the default file. then if you patch or run the settings from launcher it will replace your fallout.ini and falloutPrefs.ini with settings from the fallout_default.ini. Convoluted and broken if you ask me.