Also: In CC in Honolulu, I would love to know what
is being said when the family first views the new arrival "wrong flavor"! I'm sure it's not the rumor I've heard: "I told Birmingham to stay away from Ling!"

According to Peter X. Feng, Associate Professor of film, ethnic, and cultural studies at the University of Delaware, actor Philip Ahn speaks Korean, not Chinese in a Charlie Chan movie.

It's in the film "Charlie Chan in Honolulu" (1938) -- where Philip Ahn is supposed to be Charlie Chan's son-in-law. There's a scene where he gets very excited and speaks in Chinese, except it's Korean.

[source: Twitch - TCM: Asian Images In Film - Interview with Peter X. Feng.]