Burn, sadly, was not at the panel, but he was listed on the website. I'm guessing there was a last minute change or something.

Since JB wouldn't have noticed the mike being turned down--do you mean they turned it down when other people were speaking?

Yep. The rule of thumb is to only have one mic up at a time, that way there's less chance for feedback or cross-talk. And generally when they use handheld mics, you turn the mic down so there's no sound of it getting put down on the table. However, they had the mics set up on little stands (which I noticed the next day at the SGA panel), so technically they could have left JB podded up, or at least halfway up. I think they just forgot. You kind of get into a fugue state behind those controls at times.