Prevent homepods controlling music

When I send music to my homepods from my iPad sometimes the homepods take control but I do not know why. This usually manifests itself when I then use my iPad to change/pause the music … only to discover that it is not play … the Homepods have taken control.

How do I stop this peculiar behaviour from ever happening?

Background: IMHO, Homepods (not mini!) are reasonable airplay targets (in terms of sound quality). They are a total mess in every other sense. Siri understands little. Siri has been disabled. Handoff has been disabled. I have my iPad or iPhone in my hand already … there is no reason for the existence of ‘smart’ in Homepods. They have often been known to take a siri request from my phone when in the same room and then tell me that it cannot do something … I should use a phone!!!

Related question. iPhones and iPads keep dropping connection with the HomePods if the music is paused for more than a couple of minutes … but my macBook does not. The latter is obviously the desired workflow … I do not want to keep selecting the HomePods every time I press play! How can I make the iOS devises work correctly?