Apple tv airplay and tv speakers issue

I have an apple tv 4k connected through a Yamaha 5.1 receiver. I have recently added an airplay 2 compatible Sonos speaker to our back porch with the hopes of being able to stream Apple music, Sirius xm, etc between both the Yamaha 5.1 speakers and the Sonos on the back porch at the same time to create a multi room listening type set up.

For the first few months I was able to get audio to play from both at the same time when playing through Apple Music via the apple tv app, however any time I try to play through the Sirius xm Apple tv app it will only play on the Sonos when both the tv speakers and sonos are selected as the speaker outputs. If I uncheck the sonos speaker the audio comes back through the Yamaha receiver again no problem. Now when I try to play using Apple music the same thing is happening that has been happening with Sirius, when it worked just fine for the first few months.

I play music directly through the apps downloaded on Apple tv, not through my phone.

Am I missing something obvious that is causing this issue?