Many Channels Not Scanning

I am getting an error of "invalid character '<' looking for beginning of value" on many channels. It seems to be the Viacom owned ones. They work directly on each site.

It's working now.

I am currently having the same issue for the NFL Network channel using SlingTV. Did you do anything in particular to get your "invalid character" channels working?

It fixed itself after a few minutes. I rescanned the channels and it was finally fixed.