Thank you for that advice! I’m going to file it away for now, as I seem to be streaming with DVD, Apple TV box, Roku box, even the local TV connection. AIEEEEEEYAH it was a twisty puzzle for my husband to work out. On top of the solution posed above, we had to make another change: now he has the streamer coming out of a Marantz audio/video receiver (which is connected to ELEVEN speakers and about 10 video inputs, from game players to cable to DVD, etc.,)
If anyone ever deserved a Nobel Peace Prize in the category of preserving peace and sanity in the home theatre room, it’s my dear hubs. The whole issue with getting the stoopid Phonak streamer connected to something - anything! - in that wizard’s closet to enable me to stream from any source was just unbelievably complicated.
Hubs read the Marantz manual late last night, and would not rest till we jerry-rigged the dang streamer to it. Failed handheld remote (with fresh batteries inside) and everything but Martians landing is what we had to contend with. 
P.S. I have to add that we bought this house fully-furnished … including the evil wizard’s closet packed with what-all.