Siri voice volume on HomePod

P.S.

Two useful commands that I just noticed:

"Always speak quieter."

and

"Hey Siri, turn on automatic Siri volume," or "Hey Siri, turn off automatic Siri volume."

From this article.

Try " hey siri make your speaking volume 20%"!

...Or even "Hey Siri - at nighttime turn your speaking volume to 20%"

It might work as Siri seemed to acknowledge this request but it is daylight here.

It doesn’t appear to work as desired. You can let Apple know: Feedback - HomePod - Apple

Yes to this. I've recently noticed Siri saying that she "automatically" adjusts the speaking volume, which is extremely annoying at night when I basically whisper to issue commands and need the lowest possible response so as not to wake up the whole house.

There really should be a night mode for sounds from Siri that you can set, like you can set DND or Night Shift for alerts and screen colour. Then you could use it to limit the speaking voice volume at any times of day, or all day.

More fine tuned control of this could easily just be a preference in Home app too.