I too didn't have a problem until last night with the webcast.
I ended up downloading the Windows Media Player (don't know if it was 11) that was on the top of the live event page, http://fightingsioux.xosn.com/liveEvents/l...DB_OEM_ID=13500
I only got a black screen for awhile but after leaving the site and going back to it a couple of times I got video and audio. I also clicked on every right click pop up because I was getting frustrated and didn't know what else to do . I have Firefox too. I don't really know how I got it to work but didn't get anything until I down loaded the Windows Media player. I thought I always had it but maybe after I switched to Firefox something needed tweaking.