Many iOS apps cause my MFi hearing aids to continuously stream a silent stream

So when I launch Shazam, or Spotify, or as of a few weeks ago Sonos, my hearing aids will immediately be placed into 'streaming audio' mode, and send a silent stream to my hearing aids. This persists until I kill the app by flicking it out of the app list.

This is more annoying for MFi hearing aid users than it sounds, as streaming mode replaces the outside world - so while the app is running, you can no longer hear people talking to you, or what your smart speakers are doing, in particular what volume you're setting them to.

The only practical workaround I've found is to temporarily disable bluetooth each time I run one of these apps, and reenable it once I'm done changing the volume or whatever.

Why is this growing set of apps causing my hearing aids to start streaming silently at me ?

Is it a bug in iOS, or some unfortunate pattern that app programmers are using ?

Is there anything I can do at the iOS level to stop it ?

(My MFi hearing aids are in Apple's list of supported devices. Everything otherwise works fine.)

Thanks !