HomePod mini will not keep the Siri volume I set
When I change Siri response volume on HomePod mini, they immediately return to default level. Any?
HomePods own volume seems fairly tightly bound to media volume. You can sometimes appear to get success with "Hey Siri, change your volume to X%", but it doesn't seem to hold. Use Feedback - HomePod - Apple to let Apple know how you think things ought to work.
tt2