Learn the language of a place and pronounce it accordingly.
I live in a country with 3 language "zones" (Americans: Think of Canada with english and french parts). It's just so emberassing to hear the navigation system saying "lachaudefonds" when it should say "La Sho dfon" - and street names are even worse.
All it needs is someone making language borders on a map and switch the pronounciation. Can be done in a day for concerned countries.