Screen shot of error

Maybe Firefox codec isn't compatible with the site. Also you should contact the site and ask what's the preferred Browser to access the site as well.

Does it still happen in Troubleshoot Mode?

Could be something like this problem with playing Icecast streams where the stream is closed after playing a possible intro.

• 1843003 - Icecast streams w/ intro now have no stuttering intro but never play the stream