Polk Assist as part of Google Home speaker group

Hi All,

I have just received my Polk Assist smart Speaker. All is good as far as being a part of my Google Home "network" which consists of 3 Google nest Minis, one Chromecast, and a Google nest hub. The Polk controls my lights perfectly, so all is good there, and I appear to have successfully added the Polk to my speaker group. However, music refuses to play on the Polk when I cast the music to my "all speakers" group.

I am initiating the playing of the music via the Google Hub and music plays on all of the Nest Minis, the Hub and my Chromecast, just not the Polk.

Any suggestions?