Something to note, when i go to http://nbc.com/live i first get a blank page with only the text:
adobe-pass-2.55.1.2-4120167
Then, after several secs, it re-directs to page to select Provider, I click Xfinity.
I am amble to login fine.
It then loads the page with Guide.
Click a channel, it shows the Xfinity login screen again.
login again.
it then loads the channel stream.
my Xfinity creds are working everywhere, except for channels...so, has to be a Channels issue. maybe url changed or soemthing in the authen process that devs need to adjust...