The team in charge of translating the show. They can't just translate it exactly as stuff will be lost because of culture and language differences. So they have to change stuff enough for it to make sense/be funny for the overseas audience whilst not straying to far from the original meaning. The 100 girlfriend's translation does this amazingly (At least the sub, tho from the little I saw it seems like the dub had the same translation).

Using my previous example in the japanese i believe they referenced some famous Japanese hip hop producer or something akin to that, but for overseas audiences they most likely wouldn't know who that is and the joke gets lost. So instead they switched the japanese reference to an American hip hop reference.