“Each of these devices contains Chinese movies and songs. North Korean students accept them uncritically, enabling Chinese culture to shape our lifestyle to a much greater degree than before. An increasing number of younger people are studying Chinese so they can understand these programs without subtitles,” the source said.

No surprise since there isn't much entertainment available for North Korean students. It's the same reason why Japanese manga and anime became so popular worldwide, there's just not much competition in the field.