Comcast (complete dickbags) block almost everything on AndroidTV, so I'm forced to Google Cast HBOGo from my phone to my Mi Box.
What's really odd to me is that the quality doesn't seem to be any worse than when I would watch HBOGo directly through my old FireStickTV. ie, it still looks noticeably better than the not-so-great, low bitrate MPEG2 1080i stream that I get through my "HD" cable box from Comcast.
I hated Comcast too. You should check out Playstation Vue (don't need a Playstation for it). There is also DirectTV Now that is already out and Hulu Live channels coming out. Google live tv was mentioned before, and I believe there is another one or two big brands jumping into live TV streaming. All are much cheaper and I can only speak for Vue, but its really good.
I have PS Vue with Showtime (HBO available) through the Mi Box and saved a ton of money over basic Comcast. Great quality too.
Comcast's BS with limiting access to Android TV apps is the exact reason I canceled HBO through Comcast and switched to HBO Now. Same price, same content, no need to mess around with casting anymore.
Has anybody else tried casting from the hoopladigital app to their mi BOX...
I cant seem to get it to work, but it works without issue on my regular chromecast.
likewise, play movies work fine when played from android tv app. but if i cast them from my phone, they play for a minute or 2 and then sto with an error saying "were having trouble playing this at this time Error 2"
That's because the "cast" in Chromecast is a bit of a misnomer for most apps. Only when you are, say, casting a webpage from Chrome to your TV is it being encoded and transmitted to your Mi Box. Otherwise when using a Chromecast enabled app like HBO Go, YouTube, Netflix, etc, you are just controlling it from your phone and instructing your device (Chromecast, Mi Box, whatever) to get the stream. Your phone is nothing more than a remote control at that point.