There’s also Apple Music but neither Amazon HD or Apple Music can be played natively by Naim devices in hi-res. Apple Music requires jumping through hoops to try to play hi-res using external DACs hooked to Macs/iPhones or iPads. Airplay maxes out at CD quality currently but in practice we are not even seeing that. I assume you can Chromecast ‘hires’ from an Amazon HD player but as noted above gapless is an issue - try it with your Qobuz trial. I’d at least trial Amazon HD if you can for free as you may prefer the catalogue.
Finally, I’m not entirely convinced hi-res is a huge game changer, it’s just one of those things that logically more is better, but in practice…
Qobuz user here, I’ve bough a lot of hi-res stuff from them but when it comes to streaming it’s really hard to know if titles have been remastered for the platform, so things may simply be different due to different mastering/remastering compared to CDs or vinyl.
Amazon via Chromecast isn’t hd or even lossless last time I checked so beware, not sure that’s changed at all. Apple Music is AirPlay only so has all the caveats of that. Qobuz or Tidal are the best bet with hifi as they are properly supported.
Still says HD is not supported via Chromecast so you will get mp3 only for Amazon music on Naim.
The WiIM Mini streamer supports bit perfect Amazon Music up to 24/192 from its optical SPDIF output using the preferred Amazon MRM stack as mentioned in an earlier “Amazon HD streaming issues”thread here, both from the related WiiM app and using AlexaCast from the Amazon Music app itself. It also supports Qobuz, Tidal, Deezer etc.
Linkplay are the first to achieve casting from the Amazon Music app from what I can see, and from a small streamer than can be picked up for around £90.
I wish Amazon would play nicely with other manufacturers like Naim, Linn etc as they seem to have been doing with Linkplay. Until they do, a WiiM Mini feeding your system might be a viable alternative if you wish to use or try lossless Amazon Music.
I should also have mentioned that the latest beta firmware for the WiIM Mini is also looking to perform the first unfold of Tidal MQA (up to 24/96 iirc, but I’m not a Tidal user/ fan so could be wrong there), so that may also be of interest to some.