Update April 15: Obama's supposed mistaken "open mic" comments in Chicago. Sounds to me like the mic was meant to be on. I'll post more video when it's up. Since its a fundraising speech, it generally takes longer to be posted.
This live stream of the DNC event in Chicago has started-- someone, I have no idea who, is singing (update: Obama said it was Colbie Caillat). Obama is scheduled to speak at 10:30 pm eastern time.