Also - An HD badge now shows on the Now Playing screen while Sonos is playing higher quality audio - this is not showing either.

Did you tap the volume slider once to make the EQ icon appear on the right of the screen?

The HD and Ultra HD badges will only appear when listening to lossless audio on Amazon Music Unlimited playing on a supported Sonos device.

I’m using an iPad/iPhone controller and both the features you mentioned are working here when playing Amazon Music.

Screenshot attached from my iPad taken a few moments ago.

Sorry I should have mentioned to tap the volume-slider to get to the mini-EQ option, but I now see @GuitarSuperstar has covered it in his post.

Thank you both.  EQ sorted.  Don’t use Amazon.  I gather Tidal and Qobuz don’t show HiFi.

Thanks again.

Yes, it’s Amazon Music only that shows the HD/UltraHD/Atmos badge - hopefully other services will be included in the future.