Xfinity Stream Beta starts in HD and goes to SD on Roku Ultra
I recently switched to Xfinty Stream Beta from ATT TV streaming. I have 2 Roku Ultras. Internet connection is excellent, in fact one is wired by ethernet. When I start or switch channels on Xfinity Stream Beta, it starts in HD but switched back to SD in 10 seconds. ATTTV, Prime, Netflix all can stream HD and 4K with no problem. So the issues is with Xfinity Stream Beta. What am I doing wrong? Why does it keep resetting to SD after launching in HD? THanks.