Prime Video not launching with Xfinity app

Problem started last month...

If I speak into my Xfinity remote to open Prime Video, it launches with typical blue screen Prime Video logo and 3 white dots on the bottom.  After a couple of minutes the 3 dots/logo disappear but the blue screen stays and does not go away. Prime Video doesn't launch. Ive restarted every device and no change.

If I use the Samsung TV remote with a Prime button, Prime Video launches with a menu and other Prime TV programs (i.e. Thursday Night Football).  When I select the TV program (TNF) it launches but sound only from TV speakers NOT surround system.

I want to watch Prime Video with my surround sound, not TV speakers.

Comcast/Xfinity cable, Samsung TV HDMI (eARC) to Denon 5.1 surround system, Prime Member.