I got it to work today, but this time I did something different.
I did not have the Aux output selected on the stereo.
Aimed at the TV, I pressed AV, A.AUX and the stereo snapped on and music came from both BeoSound 4000 and Avant. (They aren't in the same room, but I live in a warehouse and the remote is powerful enough to operate both.)
Thanks for all of your assistance. Mardi Gras is over so I had time to attend to these types of needs. :o)