Quite often, the material we caption will have presenters playing media within the recording, such as in a lecture or conference. In cases like this, the Golden Rule is Caption Everything.
If you want to be super thorough, mark the beginning and end of media playback with (VIDEO PLAYS) or (MUSIC PLAYS) and (VIDEO ENDS) or (MUSIC ENDS). For example:
LECTURER: I’ll just get this started, hang on…
NARRATOR: It was 1962 when…
Use speaker tags such as NARRATOR:, INTERVIEWER:, WOMAN:, CHILD:, to indicate changes of speaker, or just use SPEAKER 1:, SPEAKER 2: if there’s no visual indication of who is talking. Try and keep any speaker numbering consistent throughout the media if you can.
The normal rules of captioning apply to media played within media, so revisit the Style Guide if there’s anything you’re unsure of.