How are you reaching ESPN? Through your cable provider's website, or directly from espn.com?
For several months, streaming from Comcast/xfinity using pc on a browser was heavily pixelated. On all channels, nothing could be watched. Using the Xfinity app on a Roku, image quality was clear. I never bothered checking back in on a pc, until now. PC streaming is back to normal when visiting the Xfinity Stream site under My Account. ESPN seemed fine-an MMA fight was on. Going directly to espn, and getting the ''select authorized cable provider'' prompt, PQ was fine-a little softer looking, but ok.
Have you switched browsers (which are you using) to see if the problem reoccurs?
Dazed and confused over high tech.
Sigh...Concrap. The Internet Overlord Cometh
They're not com-tastic!