Siri continually gives problems with our HomePods

Siri continually gives problems with our HomePod Mini's (5) and HomePods (2) and seems unable to do what you ask it to do. It says it is "working on it" and then nothing happens, or it says "this is taking too long" and again nothing happens. If you ask it to play music sometimes it plays and sometimes it just does not. If you ask it to lower the volume it intermittently just can't do that. Sometimes whilst playing music it just stops without reason. I often see the spinning light going on the top of the HomePods but nothing happens. We have super fast NBN broadband and all other wi-fi devices are working without any issues.

[Re-Titled by Moderator]