AirPlay stopped working

I no longer am able to play the same song on multiple HomePods located in different rooms. AirPlay will only connect to one HomePod at a time. This has only recently become a problem. All devices are running the latest operating systems. Resetting HomePods have not resolved the problem.

Full disclosure, I do use multiple mesh routers that are spread out in the house. However, each router is connected to the same master router. All devices are connected to the same 5 MHz SSID. This setup has worked fine in the past.

Any thoughts or suggestions?