This has always been a particular pet peeve for me whenever I watch the movies.
I've always found it puzzling that there was never an agreed-upon way of pronouncing the family name! It seems to change from scene to scene, and the same character may say it differently throughout the film(s).
You'd think that FFC would have dealt with this during production. That is, unless he was too preoccupied with other, more pressing matters. (Like keeping his job!)