I wasn't at last night's game, but apparently there was a mishap during the National Anthem. I saw people talking about it soon after it happened on Twitter. Apparently the San Diego Gay Men's Chorus was on the field and set to sing but instead there was an error in the control room and the voice of a woman singing the National Anthem was played, while the men stood silently and embarrassed.
It's hard to say why any track was played at all. Was there supposed to be a backing track for the chorus? Were they not supposed to sing live?